Sample records for neutron beams utilized

  1. Neutron beam testing of triblades

    SciTech Connect (OSTI)

    Michalak, Sarah E [Los Alamos National Laboratory; Du Bois, Andrew J [Los Alamos National Laboratory; Storlie, Curtis B [Los Alamos National Laboratory; Rust, William N [Los Alamos National Laboratory; Du Bois, David H [Los Alamos National Laboratory; Modl, David G [Los Alamos National Laboratory; Quinn, Heather M [Los Alamos National Laboratory; Blanchard, Sean P [Los Alamos National Laboratory; Manuzzato, Andrea [UNIV DEGLI STUDI DI PADOVA ITALY

    2010-12-16T23:59:59.000Z

    Four IBM Triblades were tested in the Irradiation of Chips and Electronics facility at the Los Alamos Neutron Science Center. Triblades include two dual-core Opteron processors and four PowerXCell 8i (Cell) processors. The Triblades were tested in their field configuration while running different applications, with the beam aimed at the Cell processor or the Opteron running the application. Testing focused on the Cell processors, which were tested while running five different applications and an idle condition. While neither application nor Triblade was statistically important in predicting the hazard rate, the hazard rate when the beam was aimed at the Opterons was significantly higher than when it was aimed at the Cell processors. In addition, four Cell blades (one in each Triblade) suffered voltage shorts, leading to their inoperability. The hardware tested is the same as that in the Roadrunner supercomputer.

  2. World record neutron beam at Los Alamos National Laboratory

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

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

  3. Beam Characterization at the Neutron Radiography Facility

    SciTech Connect (OSTI)

    Sarah Morgan; Jeffrey King

    2013-01-01T23:59:59.000Z

    The quality of a neutron imaging beam directly impacts the quality of radiographic images produced using that beam. Fully characterizing a neutron beam, including determination of the beam’s effective length-to-diameter ratio, neutron flux profile, energy spectrum, image quality, and beam divergence, is vital for producing quality radiographic images. This project characterized the east neutron imaging beamline at the Idaho National Laboratory Neutron Radiography Reactor (NRAD). The experiments which measured the beam’s effective length-to-diameter ratio and image quality are based on American Society for Testing and Materials (ASTM) standards. An analysis of the image produced by a calibrated phantom measured the beam divergence. The energy spectrum measurements consist of a series of foil irradiations using a selection of activation foils, compared to the results produced by a Monte Carlo n-Particle (MCNP) model of the beamline. Improvement of the existing NRAD MCNP beamline model includes validation of the model’s energy spectrum and the development of enhanced image simulation methods. The image simulation methods predict the radiographic image of an object based on the foil reaction rate data obtained by placing a model of the object in front of the image plane in an MCNP beamline model.

  4. Horizontal Beam Tubes - HFIR Technical Parameters | ORNL Neutron...

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

    Beam Tubes The reactor has four horizontal beam tubes that supply the neutrons to the neutron scattering instruments. Details for each beam tube and instrument can be found on...

  5. SPALLATION NEUTRON SOURCE BEAM CURRENT MONITOR ELECTRONICS.

    SciTech Connect (OSTI)

    KESSELMAN, M.

    2001-06-18T23:59:59.000Z

    The Spallation Neutron Source (SNS) to be constructed at ORNL is a collaboration of six laboratories. Beam current monitors for SNS will be used to monitor H-minus and H-plus beams ranging from the 15 mA (tune-up in the Front End and Linac) to over 60 A fully accumulated in the Ring. The time structure of the beams to be measured range from 645 nsec ''mini'' bunches, at the 1.05 MHz ring revolution rate, to an overall 1 mS long macro pulse. Beam current monitors (BCMs) for SNS have requirements depending upon their location within the system. The development of a general approach to satisfy requirements of various locations with common components is a major design objective. This paper will describe the development of the beam current monitors and electronics.

  6. Attenuation of Beaming Oscillations Near Neutron Stars

    E-Print Network [OSTI]

    M. Coleman Miller

    2000-07-17T23:59:59.000Z

    Observations with RXTE have revealed kilohertz quasi-periodic brightness oscillations (QPOs) from nearly twenty different neutron-star low-mass X-ray binaries (LMXBs). These frequencies often appear as a pair of kilohertz QPOs in a given power density spectrum. In many models the higher-frequency of these QPOs is a beaming oscillation at the frequency of a nearly circular orbit at some radius near the neutron star. In such models it is expected that there will also be beaming oscillations at the stellar spin frequency and at overtones of the orbital frequency, but no strong QPOs have been detected at these frequencies. We therefore examine the processes that can attenuate beaming oscillations near neutron stars, and in doing so extend the work on this subject that was initiated by the discovery of lower-frequency QPOs from LMXBs. Among our main results are (1)in a spherical scattering cloud, all overtones of rotationally modulated beaming oscillations are attenuated strongly, not just the even harmonics, and (2)it is possible to have a relatively high-amplitude modulation near the star at, e.g., the stellar spin frequency, even if no peak at that frequency is detectable in a power density spectrum taken at infinity. We discuss the application of these results to modeling of kilohertz QPOs.

  7. SPALLATION NEUTRON SOURCE BEAM CURRENT MONITOR ELECTRONICS.

    SciTech Connect (OSTI)

    KESSELMAN,M.; DAWSON,W.C.

    2002-05-06T23:59:59.000Z

    This paper will discuss the present electronics design for the beam current monitor system to be used throughout the Spallation Neutron Source (SNS) under construction at Oak Ridge National Laboratory. The beam is composed of a micro-pulse structure due to the 402.5MHz RF, and is chopped into mini-pulses of 645ns duration with a 300ns gap, providing a macro-pulse of 1060 mini-pulses repeating at a 60Hz rate. Ring beam current will vary from about 15ma peak during studies, to about 50Amps peak (design to 100 amps). A digital approach to droop compensation has been implemented and initial test results presented.

  8. A High Count Rate Beam Monitor for Thermal Neutrons

    SciTech Connect (OSTI)

    Barnett, Amanda [University of Tennessee, Knoxville (UTK); Crow, Lowell [ORNL; Diawara, Yacouba [ORNL; Funk, Loren L [ORNL; Hayward, J P [University of Tennessee, Knoxville (UTK); Menhard, Kocsis [European Synchrotron Radiation Facility (ESRF); Sedov, Vladislav N [ORNL

    2012-01-01T23:59:59.000Z

    Beam monitors are an important diagnostic tool in neutron science facilities. Present beam monitors use either ionization chambers in integration mode, which are slow and have no timing information, or pulse counters which can easily be saturated by high beam intensities. Neutron beam monitors indicate the number of neutrons incident on a scattering sample and allow neutron experimental data to be analyzed even when the source strength varies with time. At high flux neutron scattering facilities, neutron beam monitors with very low efficiency (10-5) are presently selected to keep the counting rate within a feasible range, even when a higher efficiency would improve the counting statistics and yield a better measurement of the incident beam. In this work, we report on a high count rate neutron beam monitor which also offers position sensitivity to provide a beam profile. This beam monitor offers good timing (less than 1 s) in addition to position resolution and will therefore improve the counting statistics at neutron energies up to 10 eV and allow moderator studies. The detector s main characteristics will be presented including its background rate, its count rate capability which is an order of magnitude higher than present counting monitors, and its efficiency for thermal neutrons.

  9. A High Count Rate Neutron Beam Monitor for Neutron Scattering Facilities

    SciTech Connect (OSTI)

    Barnett, Amanda [University of Tennessee, Knoxville (UTK); Crow, Lowell [ORNL; Diawara, Yacouba [ORNL; Hayward, J P [University of Tennessee, Knoxville (UTK); Hayward, Jason P [ORNL; Menhard, Kocsis [European Synchrotron Radiation Facility (ESRF); Sedov, Vladislav N [ORNL; Funk, Loren L [ORNL

    2013-01-01T23:59:59.000Z

    Abstract Beam monitors are an important diagnostic tool in neutron science facilities. Present beam monitors use either ionization chambers in integration mode, which are slow and have no timing information, or pulse counters which can easily be saturated by high beam intensities. At high flux neutron scattering facilities, neutron beam monitors with very low intrinsic efficiency (10-5) are presently selected to keep the counting rate within a feasible range, even when a higher efficiency would improve the counting statistics and yield a better measurement of the incident beam. In this work, we report on a high count rate neutron beam monitor. This beam monitor offers good timing with an intrinsic efficiency of 10-3 and a counting rate capability of over 1,000,000 cps without saturation.

  10. Enhancing Neutron Beam Production with a Convoluted Moderator

    SciTech Connect (OSTI)

    Iverson, Erik B [ORNL; Baxter, David V [Center for the Exploration of Energy and Matter, Indiana University; Muhrer, Guenter [Los Alamos National Laboratory (LANL); Ansell, Stuart [ISIS Facility, Rutherford Appleton Laboratory (ISIS); Gallmeier, Franz X [ORNL; Dalgliesh, Robert [ISIS Facility, Rutherford Appleton Laboratory (ISIS); Lu, Wei [ORNL; Kaiser, Helmut [Center for the Exploration of Energy and Matter, Indiana University

    2014-10-01T23:59:59.000Z

    We describe a new concept for a neutron moderating assembly resulting in the more efficient production of slow neutron beams. The Convoluted Moderator, a heterogeneous stack of interleaved moderating material and nearly transparent single-crystal spacers, is a directionally-enhanced neutron beam source, improving beam effectiveness over an angular range comparable to the range accepted by neutron beam lines and guides. We have demonstrated gains of 50% in slow neutron intensity for a given fast neutron production rate while simultaneously reducing the wavelength-dependent emission time dispersion by 25%, both coming from a geometric effect in which the neutron beam lines view a large surface area of moderating material in a relatively small volume. Additionally, we have confirmed a Bragg-enhancement effect arising from coherent scattering within the single-crystal spacers. We have not observed hypothesized refractive effects leading to additional gains at long wavelength. In addition to confirmation of the validity of the Convoluted Moderator concept, our measurements provide a series of benchmark experiments suitable for developing simulation and analysis techniques for practical optimization and eventual implementation at slow neutron source facilities.

  11. Measurement of the Fractional Thermonuclear Neutron Yield during Deuterium Neutral-Beam Injection into Deuterium Plasmas

    E-Print Network [OSTI]

    Measurement of the Fractional Thermonuclear Neutron Yield during Deuterium Neutral-Beam Injection into Deuterium Plasmas

  12. Neutron beam characterization at the Neutron Radiography Reactor (NRAD)

    SciTech Connect (OSTI)

    Imel, G.R.; Urbatsch, T.; Pruett, D.P.; Ross, J.R.

    1990-01-01T23:59:59.000Z

    The Neutron Radiography Reactor (NRAD) is a 250-kW TRIGA Reactor operated by Argonne National Laboratory and is located near Idaho Falls, Idaho. The reactor and its facilities regarding radiography are detailed in another paper at this conference; this paper summarizes neutron flux measurements and calculations that have been performed to better understand and potentially improve the neutronics characteristics of the reactor.

  13. Neutron measurements from beam-target reactions at the ELISE neutral beam test facility

    SciTech Connect (OSTI)

    Xufei, X., E-mail: xiexufei@pku.edu.cn; Fan, T. [State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Nocente, M.; Gorini, G. [Dipartimento di Fisica “G. Occhialini”, Università di Milano-Bicocca, Milano 20216 (Italy); Istituto di Fisica del Plasma “P. Caldirola”, Milano 20216 (Italy); Bonomo, F. [Consorzio RFX, Padova 35100 (Italy); Istituto Gas Ionizzati, CNR, Padova 35100 (Italy); Franzen, P.; Fröschle, M. [Max-Planck-Institut für Plasmaphysik, Garching 84518 (Germany); Grosso, G.; Tardocchi, M. [Istituto di Fisica del Plasma “P. Caldirola”, Milano 20216 (Italy); Grünauer, F. [Physics Consulting, Zorneding 85604 (Germany); Pasqualotto, R. [Consorzio RFX, Padova 35100 (Italy)

    2014-11-15T23:59:59.000Z

    Measurements of 2.5 MeV neutron emission from beam-target reactions performed at the ELISE neutral beam test facility are presented in this paper. The measurements are used to study the penetration of a deuterium beam in a copper dump, based on the observation of the time evolution of the neutron counting rate from beam-target reactions with a liquid scintillation detector. A calculation based on a local mixing model of deuterium deposition in the target up to a concentration of 20% at saturation is used to evaluate the expected neutron yield for comparison with data. The results are of relevance to understand neutron emission associated to beam penetration in a solid target, with applications to diagnostic systems for the SPIDER and MITICA Neutral Beam Injection prototypes.

  14. Diamond detector for high rate monitors of fast neutrons beams

    SciTech Connect (OSTI)

    Giacomelli, L.; Rebai, M.; Cippo, E. Perelli; Tardocchi, M.; Fazzi, A.; Andreani, C.; Pietropaolo, A.; Frost, C. D.; Rhodes, N.; Schooneveld, E.; Gorini, G. [Dipartimento di Fisica, Universita degli Studi di Milano-Bicocca, and Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano (Italy); Energy Department, Politecnico di Milano, Milano (Italy); Dipartimento di Fisica, Centro NAST, Universita degli Studi di Roma Tor Vergata, Roma (Italy); STFC, ISIS facility, Rutherford Appleton Laboratory, Chilton Didcot Oxfordshire (United Kingdom); Dipartimento di Fisica, Universita degli Studi di Milano-Bicocca, and Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano (Italy)

    2012-06-19T23:59:59.000Z

    A fast neutron detection system suitable for high rate measurements is presented. The detector is based on a commercial high purity single crystal diamond (SDD) coupled to a fast digital data acquisition system. The detector was tested at the ISIS pulsed spallation neutron source. The SDD event signal was digitized at 1 GHz to reconstruct the deposited energy (pulse amplitude) and neutron arrival time; the event time of flight (ToF) was obtained relative to the recorded proton beam signal t{sub 0}. Fast acquisition is needed since the peak count rate is very high ({approx}800 kHz) due to the pulsed structure of the neutron beam. Measurements at ISIS indicate that three characteristics regions exist in the biparametric spectrum: i) background gamma events of low pulse amplitudes; ii) low pulse amplitude neutron events in the energy range E{sub dep}= 1.5-7 MeV ascribed to neutron elastic scattering on {sup 12}C; iii) large pulse amplitude neutron events with E{sub n} < 7 MeV ascribed to {sup 12}C(n,{alpha}){sup 9}Be and 12C(n,n')3{alpha}.

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

    E-Print Network [OSTI]

    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

    2012-05-21T23:59:59.000Z

    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 efficiency > 20 % for neutrons below 4 MeV have been obtained.

  16. Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams

    E-Print Network [OSTI]

    Arimoto, Y; Igarashi, Y; Iwashita, Y; Ino, T; Katayama, R; Kitahara, R; Kitaguchi, M; Matsumura, H; Mishima, K; Oide, H; Otono, H; Sakakibara, R; Shima, T; Shimizu, H M; Sugino, T; Sumi, N; Sumino, H; Taketani, K; Tanaka, G; Tanaka, M; Tauchi, K; Toyoda, A; Yamada, T; Yamashita, S; Yokoyama, H; Yoshioka, T

    2015-01-01T23:59:59.000Z

    A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.

  17. Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams

    E-Print Network [OSTI]

    Y. Arimoto; N. Higashi; Y. Igarashi; Y. Iwashita; T. Ino; R. Katayama; R. Kitahara; M. Kitaguchi; H. Matsumura; K. Mishima; H. Oide; H. Otono; R. Sakakibara; T. Shima; H. M. Shimizu; T. Sugino; N. Sumi; H. Sumino; K. Taketani; G. Tanaka; M. Tanaka; K. Tauchi; A. Toyoda; T. Yamada; S. Yamashita; H. Yokoyama; T. Yoshioka

    2015-03-27T23:59:59.000Z

    A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.

  18. System and method for delivery of neutron beams for medical therapy

    DOE Patents [OSTI]

    Nigg, David W. (Idaho Falls, ID); Wemple, Charles A. (Idaho Falls, ID)

    1999-01-01T23:59:59.000Z

    A neutron delivery system that provides improved capability for tumor control during medical therapy. The system creates a unique neutron beam that has a bimodal or multi-modal energy spectrum. This unique neutron beam can be used for fast-neutron therapy, boron neutron capture therapy (BNCT), or both. The invention includes both an apparatus and a method for accomplishing the purposes of the invention.

  19. System and method for delivery of neutron beams for medical therapy

    DOE Patents [OSTI]

    Nigg, D.W.; Wemple, C.A.

    1999-07-06T23:59:59.000Z

    A neutron delivery system that provides improved capability for tumor control during medical therapy is disclosed. The system creates a unique neutron beam that has a bimodal or multi-modal energy spectrum. This unique neutron beam can be used for fast-neutron therapy, boron neutron capture therapy (BNCT), or both. The invention includes both an apparatus and a method for accomplishing the purposes of the invention. 5 figs.

  20. Awareness, Preference, Utilization, and Messaging Research for the Spallation Neutron Source and High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Bryant, Rebecca [Bryant Research, LLC; Kszos, Lynn A [ORNL

    2011-03-01T23:59:59.000Z

    Oak Ridge National Laboratory (ORNL) offers the scientific community unique access to two types of world-class neutron sources at a single site - the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR). The 85-MW HFIR provides one of the highest steady-state neutron fluxes of any research reactor in the world, and the SNS is one of the world's most intense pulsed neutron beams. Management of these two resources is the responsibility of the Neutron Sciences Directorate (NScD). NScD commissioned this survey research to develop baseline information regarding awareness of and perceptions about neutron science. Specific areas of investigative interest include the following: (1) awareness levels among those in the scientific community about the two neutron sources that ORNL offers; (2) the level of understanding members of various scientific communities have regarding benefits that neutron scattering techniques offer; and (3) any perceptions that negatively impact utilization of the facilities. NScD leadership identified users of two light sources in North America - the Advanced Photon Source (APS) at Argonne National Laboratory and the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory - as key publics. Given the type of research in which these scientists engage, they would quite likely benefit from including the neutron techniques available at SNS and HFIR among their scientific investigation tools. The objective of the survey of users of APS, NSLS, SNS, and HFIR was to explore awareness of and perceptions regarding SNS and HFIR among those in selected scientific communities. Perceptions of SNS and FHIR will provide a foundation for strategic communication plan development and for developing key educational messages. The survey was conducted in two phases. The first phase included qualitative methods of (1) key stakeholder meetings; (2) online interviews with user administrators of APS and NSLS; and (3) one-on-one interviews and traditional and online focus groups with scientists. The latter include SNS, HFIR, and APS users as well as scientists at ORNL, some of whom had not yet used HFIR and/or SNS. These approaches informed development of the second phase, a quantitative online survey. The survey consisted of 16 questions and 7 demographic categorizations, 9 open-ended queries, and 153 pre-coded variables and took an average time of 18 minutes to complete. The survey was sent to 589 SNS/HFIR users, 1,819 NSLS users, and 2,587 APS users. A total of 899 individuals provided responses for this study: 240 from NSLS; 136 from SNS/HFIR; and 523 from APS. The overall response rate was 18%.

  1. accelerator-based neutron beams: Topics by E-print Network

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

    nts foreseen for 2014 and 2015. Guerrero, C 2014-01-01 22 From x-ray telescopes to neutron scattering: using axisymmetric mirrors to focus a neutron beam CERN Preprints...

  2. Progress on the realization of a new GEM based neutron diagnostic concept for high flux neutron beams

    SciTech Connect (OSTI)

    Croci, G.; Tardocchi, M. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano, Italy and INFN, Sez. di Milano-Bicocca, Milano (Italy); Rebai, M.; Cippo, E. Perelli; Gorini, G. [Dipartimento di Fisica, Università degli Studi di Milano-Bicocca, Milano, Italy and INFN, Sez. di Milano-Bicocca, Milano (Italy); Cazzaniga, C. [Dipartimento di Fisica, Università degli Studi di Milano-Bicocca, Milano (Italy); Palma, M. Dalla; Pasqualotto, R.; Tollin, M. [Consorzio RFX - Associazione Euratom-Enea sulla Fusione, Padova (Italy); Grosso, G.; Muraro, A. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano (Italy); Murtas, F.; Claps, G. [INFN, Laboratori Nazionali di Frascati, Frascati (Roma) (Italy); Cavenago, M. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy)

    2014-08-21T23:59:59.000Z

    Fusion reactors will need high flux neutron detectors to diagnose the deuterium-deuterium and deuterium-tritium. A candidate detection technique is the Gas Electron Multiplier (GEM). New GEM based detectors are being developed for application to a neutral deuterium beam test facility. The proposed detection system is called Close-contact Neutron Emission Surface Mapping (CNESM). The diagnostic aims at providing the map of the neutron emission due to interaction of the deuterium beam with the deuterons implanted in the beam dump surface. This is done by placing a detector in close contact, right behind the dump. CNESM uses nGEM detectors, i.e. GEM detectors equipped with a cathode that also serves as neutron-proton converter foil. After the realization and test of several small area prototypes, a full size prototype has been realized and tested with laboratory sources. Test on neutron beams are foreseen for the next months.

  3. Neutron Emission from Beam-Injected Fast Tritons in JET Plasmas with Reversed or Monotonic Magnetic Shear

    E-Print Network [OSTI]

    Neutron Emission from Beam-Injected Fast Tritons in JET Plasmas with Reversed or Monotonic Magnetic Shear

  4. The development and evaluation of a neutron window filter facility utilizing the TAMU NSC TRIGA reactor

    E-Print Network [OSTI]

    Harding, Patricia Colleen

    1982-01-01T23:59:59.000Z

    for the degree of MASTER OF SCIENCE December 1982 Major Subject: Nuclear Engineering THE DEVELOPMENT AND EVALUATION OF A NEUTRON WINDOW FILTER FACILITY UTILIZING THE TAMU NSC TRIGA REACTOR A Thesis by PATRICIA COLLEEN HARDING Approved as to style...]. There are several methods that might be adopted to produce quasi-monoenergetic neutrons: Bragg scattering, neutr on generating nuclear reactions, radioactive sour- ces, resonance scattering and resonance or neutron fil? ters Bragg scattering from single...

  5. The development and evaluation of a neutron window filter facility utilizing the TAMU NSC TRIGA reactor 

    E-Print Network [OSTI]

    Harding, Patricia Colleen

    1982-01-01T23:59:59.000Z

    THE DEVELOPMENT AND EVALUATION OF A NEUTRON WINDOW FILTER FACILITY UTILIZING THE TAMU NSC TRIGA REACTOR A Thesis by PATRICIA COLLEEN HARDING Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE December 1982 Major Subject: Nuclear Engineering THE DEVELOPMENT AND EVALUATION OF A NEUTRON WINDOW FILTER FACILITY UTILIZING THE TAMU NSC TRIGA REACTOR A Thesis by PATRICIA COLLEEN HARDING Approved as to style...

  6. Uranium Neutron Coincidence Collar Model Utilizing Boron-10 Lined Tubes

    SciTech Connect (OSTI)

    Rogers, Jeremy L.; Ely, James H.; Kouzes, Richard T.; Lintereur, Azaree T.; Siciliano, Edward R.

    2012-09-18T23:59:59.000Z

    The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report, providing results for model development of Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) designs, is a deliverable under Task 2 of the project.

  7. Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

    E-Print Network [OSTI]

    R. Alba; M. Barbagallo; P. Boccaccio; A. Celentano; N. Colonna; G. Cosentino; A. Del Zoppo; A. Di Pietro; J. Esposito; P. Figuera; P. Finocchiaro; A. Kostyukov; C. Maiolino; M. Osipenko; G. Ricco; M. Ripani; C. M. Viberti; D. Santonocito; M. Schillaci

    2012-08-08T23:59:59.000Z

    In the framework of research on IVth generation reactors and high intensity neutron sources a low-power prototype neutron amplifier was recently proposed by INFN. It is based on a low-energy, high current proton cyclotron, whose beam, impinging on a thick Beryllium converter, produces a fast neutron spectrum. The world database on the neutron yield from thick Beryllium target in the 70 MeV proton energy domain is rather scarce. The new measurement was performed at LNS, covering a wide angular range from 0 to 150 degrees and an almost complete neutron energy interval. In this contribution the preliminary data are discussed together with the proposed ADS facility.

  8. Measurements of neutron dose equivalent for a proton therapy center using uniform scanning proton beams

    SciTech Connect (OSTI)

    Zheng Yuanshui; Liu Yaxi; Zeidan, Omar; Schreuder, Andries Niek; Keole, Sameer [ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); INTEGRIS Cancer Insititute, 5911 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Treatment Centers, 420 North Walnut Street, Bloomington, Indiana 47404 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States)

    2012-06-15T23:59:59.000Z

    Purpose: Neutron exposure is of concern in proton therapy, and varies with beam delivery technique, nozzle design, and treatment conditions. Uniform scanning is an emerging treatment technique in proton therapy, but neutron exposure for this technique has not been fully studied. The purpose of this study is to investigate the neutron dose equivalent per therapeutic dose, H/D, under various treatment conditions for uniform scanning beams employed at our proton therapy center. Methods: Using a wide energy neutron dose equivalent detector (SWENDI-II, ThermoScientific, MA), the authors measured H/D at 50 cm lateral to the isocenter as a function of proton range, modulation width, beam scanning area, collimated field size, and snout position. They also studied the influence of other factors on neutron dose equivalent, such as aperture material, the presence of a compensator, and measurement locations. They measured H/D for various treatment sites using patient-specific treatment parameters. Finally, they compared H/D values for various beam delivery techniques at various facilities under similar conditions. Results: H/D increased rapidly with proton range and modulation width, varying from about 0.2 mSv/Gy for a 5 cm range and 2 cm modulation width beam to 2.7 mSv/Gy for a 30 cm range and 30 cm modulation width beam when 18 Multiplication-Sign 18 cm{sup 2} uniform scanning beams were used. H/D increased linearly with the beam scanning area, and decreased slowly with aperture size and snout retraction. The presence of a compensator reduced the H/D slightly compared with that without a compensator present. Aperture material and compensator material also have an influence on neutron dose equivalent, but the influence is relatively small. H/D varied from about 0.5 mSv/Gy for a brain tumor treatment to about 3.5 mSv/Gy for a pelvic case. Conclusions: This study presents H/D as a function of various treatment parameters for uniform scanning proton beams. For similar treatment conditions, the H/D value per uncollimated beam size for uniform scanning beams was slightly lower than that from a passive scattering beam and higher than that from a pencil beam scanning beam, within a factor of 2. Minimizing beam scanning area could effectively reduce neutron dose equivalent for uniform scanning beams, down to the level close to pencil beam scanning.

  9. Demonstration of achromatic cold-neutron microscope utilizing axisymmetric focusing mirrors

    SciTech Connect (OSTI)

    Liu, D.; Khaykovich, B. [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States)] [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States); Hussey, D.; Jacobson, D.; Arif, M. [Physical Measurement Laboratory, NIST, Gaithersburg, Maryland 20899-8461 (United States)] [Physical Measurement Laboratory, NIST, Gaithersburg, Maryland 20899-8461 (United States); Gubarev, M. V.; Ramsey, B. D. [Marshall Space Flight Center, NASA, VP62, Huntsville, Alabama 35812 (United States)] [Marshall Space Flight Center, NASA, VP62, Huntsville, Alabama 35812 (United States); Moncton, D. E. [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States) [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States); Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States)

    2013-05-06T23:59:59.000Z

    An achromatic cold-neutron microscope with magnification 4 is demonstrated. The image-forming optics is composed of nested coaxial mirrors of full figures of revolution, so-called Wolter optics. The spatial resolution, field of view, and depth of focus are measured and found consistent with ray-tracing simulations. Methods of increasing the resolution and magnification are discussed, as well as the scientific case for the neutron microscope. In contrast to traditional pinhole-camera neutron imaging, the resolution of the microscope is determined by the mirrors rather than by the collimation of the beam, leading to possible dramatic improvements in the signal rate and resolution.

  10. Production cross section of neutron-rich isotopes with radioactive and stable beams

    E-Print Network [OSTI]

    Myeong-Hwan Mun; G. G. Adamian; N. V. Antonenko; Yongseok Oh; Youngman Kim

    2014-03-25T23:59:59.000Z

    The production cross section of neutron-rich isotopes of Ca, Zn, Te, Xe, and Pt are predicted in the diffusive multi-nucleon transfer reactions with stable and radioactive beams. With these isotopes one can treat the neutron shell evolution beyond N = 28, 50, 82, and 126. Because of the small cross sections, the production of nuclei near the neutron drip line requires the optimal choice of reaction partners and bombarding energies.

  11. Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

    E-Print Network [OSTI]

    M. Osipenko; M. Ripani; R. Alba; G. Ricco; M. Barbagallo; P. Boccaccio; A. Celentano; N. Colonna; L. Cosentino; A. Del Zoppo; A. Di Pietro; J. Esposito; P. Figuera; P. Finocchiaro; A. Kostyukov; C. Maiolino; D. Santonocito; M. Schillaci; V. Scuderi; C. M. Viberti

    2013-06-28T23:59:59.000Z

    The design of a low-power prototype of neutron amplifier recently proposed within the INFN-E project indicated the need for more accurate called for detailed data on the neutron yield produced by a proton beam with energy of about 70 MeV impinging on a thick Beryllium target. Such measurement was performed at the LNS superconducting cyclotron, covering a wide angular range from 0 to 150 degrees and a complete neutron energy interval from thermal to beam energy. Neutrons with energy above 0.5 MeV were measured by liquid scintillators exploiting their Time of Flight to determine the kinetic energy. For lower energy neutrons, down to thermal energy, a $^3$He detector was used. The obtained data are in good agreement with previous measurements at 0 degree with 66 MeV proton beam, covering neutron energies >10 MeV, as well as with measurements at few selected angles with protons of 46, 55 and 113 MeV energy. The present results extend the neutron yield data in the 60-70 MeV beam energy range. A comparison of measured yields to MCNP and Geant4 Monte Carlo simulations was performed.

  12. Mechanical Research and Development of monocrystalline silicon neutron beam window for CSNS

    E-Print Network [OSTI]

    Zhou Liang; Qu Hua-Min

    2014-11-24T23:59:59.000Z

    The monocrystalline silicon neutron beam window is one of the key components of neutron spectrometers and thin circular plate.Monocrystalline silicon is a brittle material and its strength is not constant but is consistent with the Weibull distribution. The window is designed not simply through the average strength, but according to the survival rate. Bending deformation is the main form of the window, so dangerous parts of the neutron beam window is stress-linearized to the combination of membrane stress and bending stress. According to the Weibull distribution of bending strength of monocrystalline silicon based on a large number of experimental data, finally the optimized neutron beam window is 1.5mm thick. Its survival rate is 0.9994 and its transmittance is 0.98447; it meets both physical requirements and the mechanical strength.

  13. SU-E-T-304: Study of Secondary Neutrons From Uniform Scanning Proton Beams

    SciTech Connect (OSTI)

    Islam, M [Lawrence Cancer Center, KS (United States); Zheng, Y [Procure Proton Therapy Center, Oklahoma City, OK (United States); Benton, E [Oklahoma State University, Stillwater, OK (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Secondary neutrons are unwanted byproducts from proton therapy and exposure from secondary radiation during treatment could increase risk of developing a secondary cancer later in a patient's lifetime. The purpose of this study is to investigate secondary neutrons from uniform scanning proton beams under various beam conditions using both measurements and Monte Carlo simulations. Methods: CR-39 Plastic Track Nuclear Detectors (PNTD) were used for the measurement. CR-39 PNTD has tissue like sensitivity to the secondary neutrons but insensitive to the therapeutic protons. In this study, we devised two experimental conditions: a) hollow-phantom; phantom is bored with a hollow cylinder along the direction of the beam so that the primary proton passes through the phantom without interacting with the phantom material, b) cylindrical-phantom; a solid cylinder of diameter close to the beam diameter is placed along the beam path. CR-39 PNTDs were placed laterally inside a 60X20X35 cm3 phantom (hollow-phantom) and in air (cylindrical-phantom) at various angles with respect to the primary beam axis. We studied for three different proton energies (78 MeV, 162 MeV and 226 MeV), using a 4 cm modulation width and 5cm diameter brass aperture for the entire experiment and simulation. A comparison of the experiment was performed using the Monte Carlo code FLUKA. Results: The measured secondary neutron dose equivalent per therapeutic primary proton dose (H/D) ranges from 2.1 ± 0.2 to 25.42 ± 2.3 mSv/Gy for the hollow phantom study, and 2.7 ± 0.3 to 46.4 ± 3.4 mSv/Gy for the cylindrical phantom study. Monte Carlo simulations predicated neutron dose equivalent from measurements within a factor of 5. Conclusion: The study suggests that the production of external neutrons is significantly higher than the production of internal neutrons.

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

    SciTech Connect (OSTI)

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

    1981-03-01T23:59:59.000Z

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

  15. Report of the first United States conference on utility experience with neutron noise analysis

    SciTech Connect (OSTI)

    Fry, D.N.; Horne, G.P.; Mayo, C.W.

    1984-01-01T23:59:59.000Z

    An informal meeting was held in Washington, D.C. on April 3 and 4, 1984, to discuss the current state of the art and experiences with neutron noise analysis in US pressurized water reactors (PWRs). The meeting was attended by 33 persons representing 11 utilities and 3 PWR reactor vendors as well as consultants, universities, and research laboratories. Presentations at the meeting covered several applications of neutron noise for diagnosing such things as vibrations induced by baffle jetting, detection of mechanical degradation of thermal shield supports, and electrical degradation of nuclear instrumentation channels. Twenty-one responses were obtained from a questionnaire circulated to all participants requesting their viewpoints and experiences regarding neutron noise analysis. The meeting participants concluded that a working group on neutron noise analysis should be formed to (1) establish a baseline library of neutron noise data, (2) provide a forum for communicating experiences with neutron noise surveillance, and (3) develop good practices and quality assurance procedures for neutron noise measurement and interpretation.

  16. High-Efficiency Resonant RF Spin Rotator with Broad Phase Space Acceptance for Pulsed Polarized Cold Neutron Beams

    E-Print Network [OSTI]

    P. -N. Seo; L. Barron-Palos; J. D. Bowman; T. E. Chupp; C. Crawford; M. Dabaghyan; M. Dawkins; S. J. Freedman; T. Gentile; M. T. Gericke; R. C. Gillis; G. L. Greene; F. W. Hersman; G. L. Jones; M. Kandes; S. Lamoreaux; B. Lauss; M. B. Leuschner; R. Mahurin; M. Mason; J. Mei; G. S. Mitchell; H. Nann; S. A. Page; S. I. Penttila; W. D. Ramsay; A. Salas Bacci; S. Santra; M. Sharma; T. B. Smith; W. M. Snow; W. S. Wilburn; H. Zhu

    2007-10-15T23:59:59.000Z

    We have developed a radio-frequency resonant spin rotator to reverse the neutron polarization in a 9.5 cm x 9.5 cm pulsed cold neutron beam with high efficiency over a broad cold neutron energy range. The effect of the spin reversal by the rotator on the neutron beam phase space is compared qualitatively to RF neutron spin flippers based on adiabatic fast passage. The spin rotator does not change the kinetic energy of the neutrons and leaves the neutron beam phase space unchanged to high precision. We discuss the design of the spin rotator and describe two types of transmission-based neutron spin-flip efficiency measurements where the neutron beam was both polarized and analyzed by optically-polarized 3He neutron spin filters. The efficiency of the spin rotator was measured to be 98.0+/-0.8% on resonance for neutron energies from 3.3 to 18.4 meV over the full phase space of the beam. As an example of the application of this device to an experiment we describe the integration of the RF spin rotator into an apparatus to search for the small parity-violating asymmetry A_gamma in polarized cold neutron capture on para-hydrogen by the NPDGamma collaboration at LANSCE.

  17. Production cross sections of neutron rich isotopes from a 82Se beam

    E-Print Network [OSTI]

    Tarasov, O B; Amthor, A M; Bandura, L; Baumann, T; Bazin, D; Berryman, J S; Chubarian, G; Fukuda, N; Gade, A; Ginter, T N; Hausmann, M; Inabe, N; Kubo, T; Pereira, J; Portillo, M; Sherrill, B M; Stolz, A; Sumithrarachchi, C; Thoennessen, M; Weisshaar, D

    2012-01-01T23:59:59.000Z

    Production cross sections for neutron-rich nuclei from the fragmentation of a 82Se beam at 139 MeV/u were measured. The longitudinal momentum distributions of 122 neutron-rich isotopes of elements $11 \\le Z \\le 32$ were determined by varying the target thickness. Production cross sections with beryllium and tungsten targets were determined for a large number of nuclei including several isotopes first observed in this work. These are the most neutron-rich nuclides of the elements $22 \\le Z \\le 25$ (64Ti, 67V, 69Cr, 72Mn). One event was registered consistent with 70Cr, and another one with 75Fe. A one-body Qg systematics is used to describe the production cross sections based on thermal evaporation from excited prefragments. The current results confirm those of our previous experiment with a 76Ge beam: enhanced production cross sections for neutron-rich fragments near Z=20.

  18. Production cross sections of neutron rich isotopes from a 82Se beam

    E-Print Network [OSTI]

    O. B. Tarasov; D. J. Morrissey; A. M. Amthor; L. Bandura; T. Baumann; D. Bazin; J. S. Berryman; G. Chubarian; N. Fukuda; A. Gade; T. N. Ginter; M. Hausmann; N. Inabe; T. Kubo; J. Pereira; M. Portillo; B. M. Sherrill; A. Stolz; C. Sumithrarachchi; M. Thoennessen; D. Weisshaar

    2012-09-06T23:59:59.000Z

    Production cross sections for neutron-rich nuclei from the fragmentation of a 82Se beam at 139 MeV/u were measured. The longitudinal momentum distributions of 122 neutron-rich isotopes of elements $11 \\le Z \\le 32$ were determined by varying the target thickness. Production cross sections with beryllium and tungsten targets were determined for a large number of nuclei including several isotopes first observed in this work. These are the most neutron-rich nuclides of the elements $22 \\le Z \\le 25$ (64Ti, 67V, 69Cr, 72Mn). One event was registered consistent with 70Cr, and another one with 75Fe. A one-body Qg systematics is used to describe the production cross sections based on thermal evaporation from excited prefragments. The current results confirm those of our previous experiment with a 76Ge beam: enhanced production cross sections for neutron-rich fragments near Z=20.

  19. SICANE: a Detector Array for the Measurement of Nuclear Recoil Quenching Factors using Monoenergetic Neutron Beam

    E-Print Network [OSTI]

    E. Simon; L. Berge; A. Broniatowski; R. Bouvier; B. Chambon; M. De Jesus; D. Drain; L. Dumoulin; J. Gascon; J. P. Hadjout; A. Juillard; O. Martineau; C. Pastor; M. Stern; L. Vagneron

    2002-12-20T23:59:59.000Z

    SICANE is a neutron scattering multidetector facility for the determination of the quenching factor (ratio of the response to nuclear recoils and to electrons) of cryogenic detectors used in direct WIMP searches. Well collimated monoenergetic neutron beams are obtained with inverse (p,n) reactions. The facility is described, and results obtained for the quenching factors of scintillation in NaI(Tl) and of heat and ionization in Ge are presented.

  20. INVESTIGATION OF NEW MATERIALS AND DETECTORS USING THE ELECTROSTATIC ACCELERATOR AND NEUTRON GENERATOR BEAMS

    E-Print Network [OSTI]

    Titov, Anatoly

    GENERATOR BEAMS V.M.Lebedev, V.A.Smolin, I.M.Kotina, A.G.Krivchitch, Yu.F.Biryulin 1 , V.I.Ivanov­Omskii 1 with the energy of 1.6 MeV and a neutron generator with 14 MeV monoenergetic neutrons [1-3] - were used for a wide was very actually, especially, of oxygen content due to the largest mobility of these atoms in YBa 2 Cu 3 O

  1. The development and demonstration of a thermal neutron radiography facility utilizing the TAMU NSC TRIGA reactor

    E-Print Network [OSTI]

    Lorenz, Robert Wayne

    1972-01-01T23:59:59.000Z

    an object without permanently changing or destroying the object being inspected. X ? rays and gamma rays are probably the most widely used radiations in the above applications; however, the use of beams of neutrons is becoming more prevalent. Radiography... useful results, the attenuation of radiation per unit thickness of material must depend upon the physical or atomic characteristics of the material. X-rays and gamma rays are absorbed within the objects by various interactions with the elec- tronic...

  2. Production of very neutron-rich nuclei with a 76Ge beam

    E-Print Network [OSTI]

    O. B. Tarasov; M. Portillo; A. M. Amthor; T. Baumann; D. Bazin; A. Gade; T. N. Ginter; M. Hausmann; N. Inabe; T. Kubo; D. J. Morrissey; A. Nettleton; J. Pereira; B. M. Sherrill; A. Stolz; M. Thoennessen

    2009-08-26T23:59:59.000Z

    Production cross sections for neutron-rich nuclei from the fragmentation of a 76Ge beam at 132 MeV/u were measured. The longitudinal momentum distributions of 34 neutron-rich isotopes of elements 13 Production cross sections with beryllium and tungsten targets were determined for a large number of nuclei including 15 isotopes first observed in this work. These are the most neutron-rich nuclides of the elements 17 production cross sections based on thermal evaporation from excited prefragments. Some of the fragments near 58Ca show anomalously large production cross sections.

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

    SciTech Connect (OSTI)

    Liang, J Felix [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    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.

  4. Production of very neutron-rich nuclei with a 76Ge beam

    E-Print Network [OSTI]

    Tarasov, O B; Amthor, A M; Baumann, T; Bazin, D; Gade, A; Ginter, T N; Hausmann, M; Inabe, N; Kubo, T; Morrissey, D J; Nettleton, A; Pereira, J; Sherrill, B M; Stolz, A; Thoennessen, M

    2009-01-01T23:59:59.000Z

    Production cross sections for neutron-rich nuclei from the fragmentation of a 76Ge beam at 132 MeV/u were measured. The longitudinal momentum distributions of 34 neutron-rich isotopes of elements 13 Production cross sections with beryllium and tungsten targets were determined for a large number of nuclei including 15 isotopes first observed in this work. These are the most neutron-rich nuclides of the elements 17 production cross sections based on thermal evaporation from excited prefragments. Some of the fragments near 58Ca show anomalously large production cross sections.

  5. Comparisons on thin and thick neutron target for low energy proton beam

    SciTech Connect (OSTI)

    Zhong, B.; Yu, G.; Wang, X.; Wang, K. [Dept. of Engineering Physics, Tsinghua Univ., Beijing 100084 (China)

    2012-07-01T23:59:59.000Z

    As the progress on accelerator physics and neutronics, the compact neutron sources driven by low energy and high intensity beam are becoming extensively developed and researched all around the world. The neutron target of an accelerator driven neutron source is one of the key components, and the stability of the neutron target affect the operation and performance of the neutron facility. When a low energy proton is projected to the beryllium target, the main reaction is the inelastic scattering between the proton and extra-nuclear electrons. As the decreasing of proton energy, the rate of elastic scattering between proton and target nucleus begins to increase. When the energy of proton is very low, the pickup charge reaction begins to appear. Focus on the problems brought by high intensity proton beam such as proton implantation, radiation damages, heat deposition and gas production, we performed sufficient numerical simulations for both thin and thick target determined by proton range. The results show that the critical problem for thick target is the proton implantation, causing the forming of bubbles and beryllium flaked in vacuum. The thin target sacrifices a little neutron yield, but avoid the proton stopped in target, and decrease the radiation damage and energy deposition. (authors)

  6. The extraction of a mono-energetic neutron beam of maximum intensity from a nuclear reactor

    E-Print Network [OSTI]

    Snow, Edward Clark

    1965-01-01T23:59:59.000Z

    / January 1965 TABLE OF CONTENTS CHAPTER PAGE INTRODUCTION 1. Ob j ec tive 2. Design Considerations DESIGN AND CONSTRUCTION 1. Collimator and Plug 2. Extension Tube 3. Crystal and Mount 4. Servo Control System 5. Assembly 13 17 24 30 III.... CONCLUSION 32 BIBLIOGRAPHY 33 LIST OF FIGURES FIGURE PAGE The intensity versus wavelength distribution for a collimated neutron beam emerging from a reactor. Collimator tube in a shielding plug in a reactor beam-port. Experimental layout at Oak Ridge...

  7. Development of a fast neutron therapy beam placement film technique

    E-Print Network [OSTI]

    Baron, Robert Layton

    1971-01-01T23:59:59.000Z

    used are surgery and radiotherapy. High energy X rays and gamma rays are most often used when radio- therapy is required, but new interest in the use of other types of radiation has recently been generated. One of the first characteristics... of neutron radiation to be noted by Chadwick in 1932 was its ability to penetrate matter in manner similar to X rays (2). Although the results of Stone and his colleagues (3-5) caused Stone to recommend that neutrons not be used in cancer therapy, more...

  8. advanced neutron beam: Topics by E-print Network

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

    by several orders of magnitude compared to the best beam experiments performed in the 1970's and can compete with the sensitivity of UCN experiments. Piegsa, F M 2013-01-01 23 New...

  9. Neutron Halo Isomers in Stable Nuclei and their Possible Application for the Production of Low Energy, Pulsed, Polarized Neutron Beams of High Intensity and High Brilliance

    E-Print Network [OSTI]

    D. Habs; M. Gross; P. G. Thirolf; P. Böni

    2010-09-30T23:59:59.000Z

    We propose to search for neutron halo isomers populated via $\\gamma$-capture in stable nuclei with mass numbers of about A=140-180 or A=40-60, where the $4s_{1/2}$ or $3s_{1/2}$ neutron shell model state reaches zero binding energy. These halo nuclei can be produced for the first time with new $\\gamma$-beams of high intensity and small band width ($\\le$ 0.1%) achievable via Compton back-scattering off brilliant electron beams thus offering a promising perspective to selectively populate these isomers with small separation energies of 1 eV to a few keV. Similar to single-neutron halo states for very light, extremely neutron-rich, radioactive nuclei \\cite{hansen95,tanihata96,aumann00}, the low neutron separation energy and short-range nuclear force allows the neutron to tunnel far out into free space much beyond the nuclear core radius. This results in prolonged half lives of the isomers for the $\\gamma$-decay back to the ground state in the 100 ps-$\\mu$s range. Similar to the treatment of photodisintegration of the deuteron, the neutron release from the neutron halo isomer via a second, low-energy, intense photon beam has a known much larger cross section with a typical energy threshold behavior. In the second step, the neutrons can be released as a low-energy, pulsed, polarized neutron beam of high intensity and high brilliance, possibly being much superior to presently existing beams from reactors or spallation neutron sources.

  10. Voluminous D2 source for intense cold neutron beam production at the ESS

    E-Print Network [OSTI]

    Esben Klinkby; Konstantin Batkov; Ferenc Mezei; Troels Schønfeldt; Alan Takibayev; Luca Zanini

    2014-01-23T23:59:59.000Z

    The development of the flat moderator concept at ESS recently opened up the possibility that a single flat moderator above the target could serve all the scattering instruments, that rely on high brightness. This would allow for the introduction of a fundamentally different moderator below the target for the complementary needs of certain fundamental physics experiments. To facilitate experiments depending on the total number of neutrons in a sizable beam, the option of a voluminous D2 moderator, in a large cross-section extraction guide is discussed and its neutronic performance is assessed.

  11. Voluminous D2 source for intense cold neutron beam production at the ESS

    E-Print Network [OSTI]

    Klinkby, Esben; Mezei, Ferenc; Schønfeldt, Troels; Takibayev, Alan; Zanini, Luca

    2014-01-01T23:59:59.000Z

    The development of the flat moderator concept at ESS recently opened up the possibility that a single flat moderator above the target could serve all the scattering instruments, that rely on high brightness. This would allow for the introduction of a fundamentally different moderator below the target for the complementary needs of certain fundamental physics experiments. To facilitate experiments depending on the total number of neutrons in a sizable beam, the option of a voluminous D2 moderator, in a large cross-section extraction guide is discussed and its neutronic performance is assessed.

  12. Nuclear Waste Removal Using Particle Beams Incineration with Fast Neutrons

    E-Print Network [OSTI]

    Revol, Jean Pierre Charles

    1997-01-01T23:59:59.000Z

    The management of nuclear waste is one of the major obstacles to the acceptability of nuclear power as a main source of energy for the future. TARC, a new experiment at CERN, is testing the practicality of Carlo Rubbia's idea to make use of Adiabatic Resonance Crossing to transmute long-lived fission fragments into short-lived or stable nuclides. Spallation neutrons produced in a large Lead assembly have a high probability to be captured at the energies of cross-section resonances in elements such as 99Tc, 129I, etc. An accelerator-driven sub-critical device using Thorium (Energy Amplifier) would be very effective in eliminating TRansUranic elements which constitute the most dangerous part of nuclear waste while producing from it large amounts of energy. In addition, such a system could transform, at a high rate and little energetic cost, long-lived fission fragments into short-lived elements.

  13. A new measurement of Beam Asymmetry in Pion Photoproduction from the Neutron using CLAS

    SciTech Connect (OSTI)

    D. Sokhan, D. Watts, D. Branford, F. Klein

    2010-08-01T23:59:59.000Z

    We present a preliminary analysis of the photon beam asymmetry observable (Sigma) from the photoproduction reaction channel gamma+ n -> p + pi-. This new data was obtained using the near-4pi CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory, USA, employing a linearly polarised photon beam with an energy range 1.1 - 2.3 GeV. The measurement will provide new data to address the poorly established neutron excitation spectrum and will greatly expand the sparse world data-set both in energy and angle.

  14. Scattering Theory When an x-ray beam (or neutron or light) passes through a material with

    E-Print Network [OSTI]

    Beaucage, Gregory

    Scattering Theory When an x-ray beam (or neutron or light) passes through a material radiation is scattered in directions that differ from that of the incident beam. Scattering arises since x of scattered radiation resulting from this process bears a direct relationship to the structure (the pattern

  15. Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600. Proposals for beam time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR)

    E-Print Network [OSTI]

    Pennycook, Steve

    Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600. Proposals for beam Wildgruber, wildgrubercu@ornl.gov. VISION CallforProposals neutrons.ornl.gov Neutron Scattering Science - Oak time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR) and Spallation Neutron Source

  16. TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 2 DF WASTE LINE REMOVAL, BNL

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-07-09T23:59:59.000Z

    5098-SR-02-0 PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 2 DF WASTE LINE REMOVAL, BROOKHAVEN NATIONAL LABORATORY

  17. Analyses of engineering-oriented neutronics integral experiments utilizing beryllium in various configurations with 14 MeV point source

    SciTech Connect (OSTI)

    Youssef, M.; Abdou, M.; Kumar, A. [Univ. of California, Los Angeles, CA (United States)] [and others

    1994-12-31T23:59:59.000Z

    The analysis of integral experiments on tritium breeding rate (TPR), in-system spectrum, and several reaction rates inside a Li{sub 2}O test assembly were performed in a closed geometry with a 14 MeV point source in which beryllium has been extensively utilized as a neutron multiplier. This activity was part of the USDOE/JAERI Collaborative Program on Fusion Blanket Neutronics with the objective of verifying the present neutron transport codes and databases in predicting key design parameters such as TPR. The test assembly itself (with dimension of {approximately}87 cm x {approximately}87 cm x 60 cm) is located at one end of a Li{sub 2}CO{sub 3} enclosure and the neutron point source is located at a distance of {approximately}78 cm from the assembly. The enclosure is surrounded from the outside by polyethylene layer (5 cm-thick) to minimize the neutron wall-room effect.

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

    SciTech Connect (OSTI)

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

    2008-01-01T23:59:59.000Z

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

  19. Neutron beam irradiation study of workload dependence of SER in a microprocessor

    SciTech Connect (OSTI)

    Michalak, Sarah E [Los Alamos National Laboratory; Graves, Todd L [Los Alamos National Laboratory; Hong, Ted [STANFORD; Ackaret, Jerry [IBM; Sonny, Rao [IBM; Subhasish, Mitra [STANFORD; Pia, Sanda [IBM

    2009-01-01T23:59:59.000Z

    It is known that workloads are an important factor in soft error rates (SER), but it is proving difficult to find differentiating workloads for microprocessors. We have performed neutron beam irradiation studies of a commercial microprocessor under a wide variety of workload conditions from idle, performing no operations, to very busy workloads resembling real HPC, graphics, and business applications. There is evidence that the mean times to first indication of failure, MTFIF defined in Section II, may be different for some of the applications.

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

    SciTech Connect (OSTI)

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

    1997-12-01T23:59:59.000Z

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

  1. LASER TRIGGERED GAS SWITCHES UTILIZING BEAM TRANSPORT THROUGH 1 MO-cm DEIONIZED WATER.

    SciTech Connect (OSTI)

    Woodworth, Joseph Ray; Lehr, Jane [Sandia National Laboratories, Albuquerque, NM; Blickem, James R.; Wallace, Zachariah R.; Anaya, Victor Jr; Corley, John P; Lott, John; Hodge, Keith; Zameroski, Nathan D. [Sandia National Laboratories, Albuquerque, NM

    2005-11-01T23:59:59.000Z

    We report on the successful attempts to trigger high voltage pressurized gas switches by utilizing beam transport through 1 MO-cm deionized water. The wavelength of the laser radiation was 532 nm. We have investigated Nd: YAG laser triggering of a 6 MV, SF6 insulated gas switch for a range of laser and switch parameters. Laser wavelength of 532 nm with nominal pulse lengths of 10 ns full width half maximum (FWHM) were used to trigger the switch. The laser beam was transported through 67 cm-long cell of 1 MO-cm deionized water constructed with anti reflection UV grade fused silica windows. The laser beam was then focused to form a breakdown arc in the gas between switch electrodes. Less than 10 ns jitter in the operation of the switch was obtained for laser pulse energies of between 80-110 mJ. Breakdown arcs more than 35 mm-long were produced by using a 70 cm focusing optic.

  2. Non-streaming high-efficiency perforated semiconductor neutron detectors, methods of making same and measuring wand and detector modules utilizing same

    DOE Patents [OSTI]

    McGregor, Douglas S. (Riley, KS); Shultis, John K. (Manhattan, KS); Rice, Blake B. (Manhattan, KS); McNeil, Walter J. (Winnfield, KS); Solomon, Clell J. (Wichita, KS); Patterson, Eric L. (Manhattan, KS); Bellinger, Steven L. (Manhattan, KS)

    2010-12-21T23:59:59.000Z

    Non-streaming high-efficiency perforated semiconductor neutron detectors, method of making same and measuring wands and detector modules utilizing same are disclosed. The detectors have improved mechanical structure, flattened angular detector responses, and reduced leakage current. A plurality of such detectors can be assembled into imaging arrays, and can be used for neutron radiography, remote neutron sensing, cold neutron imaging, SNM monitoring, and various other applications.

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

    SciTech Connect (OSTI)

    E.M. Harpenau

    2010-12-15T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-11-03T23:59:59.000Z

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

  5. Fusion neutron generation computations in a stellarator-mirror hybrid with neutral beam injection

    SciTech Connect (OSTI)

    Moiseenko, V. E.; Agren, O. [Institute of Plasma Physics, National Science Center 'Kharkiv Institute of Physics and Technology', Akademichna St. 1, 61108 Kharkiv (Ukraine); Uppsala University, Angstroem Laboratory, Division of Electricity, Box 534, SE-7512 Uppsala (Sweden)

    2012-06-19T23:59:59.000Z

    In the paper [Moiseenko V.E., Noack K., Agren O. 'Stellarator-mirror based fusion driven fission reactor' J Fusion Energy 29 (2010) 65.], a version of a fusion driven system (FDS), i.e. a sub-critical fast fission assembly with a fusion plasma neutron source, is proposed. The plasma part of the reactor is based on a stellarator with a small mirror part. Hot ions with high perpendicular energy are assumed to be trapped in the magnetic mirror part. The stellarator part which connects to the mirror part and provides confinement for the bulk (deuterium) plasma. In the magnetic well of the mirror part, fusion reactions occur from collisions between a of hot ion component (tritium) with cold background plasma ions. RF heating is one option to heat the tritium. A more conventional method to sustain the hot ions is neutral beam injection (NBI), which is here studied numerically for the above-mentioned hybrid scheme. For these studies, a new kinetic code, KNBIM, has been developed. The code takes into account Coulomb collisions between the hot ions and the background plasma. The geometry of the confining magnetic field is arbitrary for the code. It is accounted for via a numerical bounce averaging procedure. Along with the kinetic calculations the neutron generation intensity and its spatial distribution are computed.

  6. Neutron range spectrometer

    DOE Patents [OSTI]

    Manglos, S.H.

    1988-03-10T23:59:59.000Z

    A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.

  7. Demonstration of achromatic cold-neutron microscope utilizing axisymmetric focusing mirrors

    E-Print Network [OSTI]

    Liu, Dazhi

    An achromatic cold-neutron microscope with magnification 4 is demonstrated. The image-forming optics is composed of nested coaxial mirrors of full figures of revolution, so-called Wolter optics. The spatial resolution, ...

  8. Beta-delayed neutron and gamma-ray spectroscopy of 17C utilizing spin-polarized 17B

    E-Print Network [OSTI]

    H. Ueno; H. Miyatake; Y. Yamamoto; S. Tanimoto; T. Shimoda; N. Aoi; K. Asahi; E. Ideguchi; M. Ishihara; H. Izumi; T. Kishida; T. Kubo; S. Mitsuoka; Y. Mizoi; M. Notani; H. Ogawa; A. Ozawa; M. Sasaki; T. Shirakura; N. Takahashi; K. Yoneda

    2013-01-31T23:59:59.000Z

    Excited states in 17C were investigated through the measurement of beta?-delayed neutrons and gamma rays emitted in the ? decay of 17B. In the measurement, three negative-parity states and two inconclusive states, were identified in 17C above the neutron threshold energy, and seven gamma-lines were identified in a beta?-delayed multiple neutron emission of the 17B ? decay. From these transitions, the beta?-decay scheme of 17B was determined. In the present work, the ?beta-NMR technique is combined with the ?-delayed particle measurements using a fragmentation-induced spin-polarized 17B beam. This new scheme allows us to determine the spin parity of beta?-decay feeding excited states based on the difference in the discrete ?beta-decay asymmetry parameters, provided the states are connected through the Gamow-Teller transition. In this work, 1/2-, 3/2-, and (5/2-) are assigned to the observed states at Ex = 2.71(2), 3.93(2), and 4.05(2) MeV in 17C, respectively.

  9. Beta-delayed neutron and gamma-ray spectroscopy of 17C utilizing spin-polarized 17B

    E-Print Network [OSTI]

    Ueno, H; Yamamoto, Y; Tanimoto, S; Shimoda, T; Aoi, N; Asahi, K; Ideguchi, E; Ishihara, M; Izumi, H; Kishida, T; Kubo, T; Mitsuoka, S; Mizoi, Y; Notani, M; Ogawa, H; Ozawa, A; Sasaki, M; Shirakura, T; Takahashi, N; Yoneda, K

    2013-01-01T23:59:59.000Z

    Excited states in 17C were investigated through the measurement of beta?-delayed neutrons and gamma rays emitted in the ? decay of 17B. In the measurement, three negative-parity states and two inconclusive states, were identified in 17C above the neutron threshold energy, and seven gamma-lines were identified in a beta?-delayed multiple neutron emission of the 17B ? decay. From these transitions, the beta?-decay scheme of 17B was determined. In the present work, the ?beta-NMR technique is combined with the ?-delayed particle measurements using a fragmentation-induced spin-polarized 17B beam. This new scheme allows us to determine the spin parity of beta?-decay feeding excited states based on the difference in the discrete ?beta-decay asymmetry parameters, provided the states are connected through the Gamow-Teller transition. In this work, 1/2-, 3/2-, and (5/2-) are assigned to the observed states at Ex = 2.71(2), 3.93(2), and 4.05(2) MeV in 17C, respectively.

  10. Lithium-6 filter for a fission converter-based Boron Neutron Capture Therapy irradiation facility beam

    E-Print Network [OSTI]

    Gao, Wei, Ph. D.

    2005-01-01T23:59:59.000Z

    (cont.) A storage system was designed to contain the lithium-6 filter safely when it is not in use. A mixed field dosimetry method was used to measure the photon, thermal neutron and fast neutron dose. The measured advantage ...

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

    SciTech Connect (OSTI)

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

    2004-09-28T23:59:59.000Z

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

  12. Determination of the approximate relative biological effectiveness (RBE) of fast neutrons, utilizing the oral mucosa of dogs as the biological indicator

    E-Print Network [OSTI]

    Roberts, Royce Elisha

    1975-01-01T23:59:59.000Z

    DETERMINATION OF THE APPROXIMATE RELATIVE BIOLOGICAL EFFECTIVENESS (RBE) OF FAST NEUTRONS, UTILIZING THE ORAL MUCOSA OF DOGS AS THE BIOLOGICAL INDICATOR A Thesis by ROYCE ELISHA ROBERTS Submitted to the Graduate College of Texas ABM..., UTILIZING THE ORAL MUCOSA OF DOGS AS THE BIOLOGICAL INDICATOR A Thesis by ROYCE ELISHA ROBERTS Approved as to style and content by: Chairman of Committee Hea epartment Member mber ember May 1975 ABSTRACT Determination of the Approximate Relative...

  13. Deformation of the very neutron-deficient rare-earth nuclei produced with the SPIRAL 76Kr radioactive beam and studied with EXOGAM + DIAMANT

    SciTech Connect (OSTI)

    Redon, N.; Guinet, D.; Lautesse, Ph.; Meyer, M.; Rosse, B.; Stezowski, O. [IPN Lyon, IN2P3/CNRS, Universite Claude Bernard Lyon-1, F-69622 Villeurbanne Cedex (France); Prevost, A. [IPN Lyon, IN2P3/CNRS, Universite Claude Bernard Lyon-1, F-69622 Villeurbanne Cedex (France); CSNSM Orsay, IN2P3/CNRS, Bat 104, F-91405 Orsay Campus (France); Nolan, P.J.; Andreoiu, C.; Boston, A.J.; Descovich, M.; Evans, A.O.; Gros, S.; Norman, J.; Page, R.D.; Paul, E.S.; Rainovski, G.; Sampson, J. [Oliver Lodge Laboratory, University of Liverpool, P.O. Box 147, Liverpool L69 7ZE (United Kingdom); France, G. de; Casandjian, J. M. [GANIL, B.P. 55027, F-14076 Caen Cedex (France)] [and others

    2004-02-27T23:59:59.000Z

    The structure of the very neutron-deficient rare-earth nuclei has been investigated in the first experiment with the EXOGAM gamma array coupled to the DIAMANT light charged particle detector using radioactive beam of 76Kr delivered by the SPIRAL facility. Very neutron-deficient Pr, Nd and Pm isotopes have been populated at rather high spin by the reaction 76Kr + 58Ni at a beam energy of 328 MeV. We report here the first results of this experiment.

  14. Simulation of neutron displacement damage in bipolar junction transistors using high-energy heavy ion beams.

    SciTech Connect (OSTI)

    Doyle, Barney Lee; Buller, Daniel L.; Hjalmarson, Harold Paul; Fleming, Robert M; Bielejec, Edward Salvador; Vizkelethy, Gyorgy

    2006-12-01T23:59:59.000Z

    Electronic components such as bipolar junction transistors (BJTs) are damaged when they are exposed to radiation and, as a result, their performance can significantly degrade. In certain environments the radiation consists of short, high flux pulses of neutrons. Electronics components have traditionally been tested against short neutron pulses in pulsed nuclear reactors. These reactors are becoming less and less available; many of them were shut down permanently in the past few years. Therefore, new methods using radiation sources other than pulsed nuclear reactors needed to be developed. Neutrons affect semiconductors such as Si by causing atomic displacements of Si atoms. The recoiled Si atom creates a collision cascade which leads to displacements in Si. Since heavy ions create similar cascades in Si we can use them to create similar damage to what neutrons create. This LDRD successfully developed a new technique using easily available particle accelerators to provide an alternative to pulsed nuclear reactors to study the displacement damage and subsequent transient annealing that occurs in various transistor devices and potentially qualify them against radiation effects caused by pulsed neutrons.

  15. Improving Natural Uranium Utilization By Using Thorium in Low Moderation PWRs - A Preliminary Neutronic Scoping Study

    SciTech Connect (OSTI)

    Gilles Youinou; Ignacio Somoza

    2010-10-01T23:59:59.000Z

    The Th-U fuel cycle is not quite self-sustainable when used in water-cooled reactors and with fuel burnups higher than a few thousand of MWd/t characteristic of CANDU reactors operating with a continuous refueling. For the other industrially mature water-cooled reactors (i.e. PWRs and BWRs) it is economically necessary that the fuel has enough reactivity to reach fuel burnups of the order of a few tens of thousand of MWd/t. In this particular case, an additional input of fissile material is necessary to complement the bred fissile U-233. This additional fissile material could be included in the form of Highly Enriched Uranium (HEU) at the fabrication of the Th-U fuel. The objective of this preliminary neutronic scoping study is to determine (1) how much HEU and, consequently, how much natural uranium is necessary in such Th-U fuel cycle with U recycling and (2) how much TRansUranics (TRU=Pu, Np, Am and Cm) are produced. These numbers are then compared with those of a standard UO2 PWR. The thorium reactors considered have a homogeneous hexagonal lattice made up of the same (Th-U)O2 pins. Furthermore, at this point, we are not considering the use of blankets inside or outside the core. The lattice pitch has been varied to estimate the effect of the water-to-fuel volume ratio, and light water as well as heavy water have been considered. For most cases, an average burnup at discharge of 45,000 MWd/t has been considered.

  16. materialsELSEVIER Journal of Nuclear Materials 233-237 (1996) 1547-1551 Deuteron beam interaction with lithium jet in a neutron source test

    E-Print Network [OSTI]

    Harilal, S. S.

    -speed flowing jet of liquid Li, as shown in Fig. 1. This system must also be capable of operating under the high tank where complete mixing occurs with the large volume of Li in the tank. Some of the concerns beam interaction with lithium jet in a neutron source test facility I A. Hassanein Argonne National

  17. Current Status and Future Works of Neutron Scattering Laboratory at BATAN in Serpong

    SciTech Connect (OSTI)

    Ikram, A. [Center of Technology for Nuclear Industrial Materials, National Nuclear Energy Agency of Indonesia (BATAN) Kawasan Puspiptek Serpong, Tangerang 15314 (Indonesia)

    2008-03-17T23:59:59.000Z

    Current status of neutron beam instruments using neutrons produced by the Multi Purpose Research Reactor--30MWth (MPR 30, RSG GA Siwabessy) located in Serpong is presented. Description of the reactor as the neutron source is mentioned briefly. There are six neutron beam tubes coming from the beryllium reflector surrounding half of the reactor core providing neutrons in the experimental hall of the reactor (XHR). Four of them are dedicated to R and D in materials science using neutron scattering techniques. Neutron Radiography Facility (NRF), Triple Axis Spectrometer (TAS) and Residual Stress Measurement (RSM) Diffractometer are installed respectively at beam tubes S2, S4 and S6. The largest neutron beam tube (S5) is exploited to accommodate two neutron guide tubes that transfer the neutrons to a neighbouring building called neutron guide hall (NGH). There are three other neutron beam instruments installed in this building, namely Small Angle Neutron Scattering (SANS) Spectrometer (SMARTer), High Resolution SANS (HRSANS) Spectrometer and High Resolution Powder Diffractometer (HRPD). In the XHR, a Four Circle and Texture Diffractometer (FCD/TD) is attached to one of the neutron guide tubes. These seven instruments were installed to utilize the neutrons for materials science research, and recently the RSM diffractometer has shown its capabilities in identifying different amount of stress left due to different treatments of welding in fuel cladding, while the SANS spectrometer is now gaining capabilities in identifying different sizes and shapes of macromolecules in polymers as well as investigations of magnetic samples. In the mean time, non-destructive tests using the NRF is gathering more confidence from some latest real time measurements eventhough there are still some shortcomings in the components and their alignments. Future works including improvement of each facility and its components, even replacement of some parts are necessary and have to be carried out carefully. A plan for developing a neutron reflectometer at one of the neutron guide in the Neutron Guide Hall is also part of the near future activities.

  18. Neutron skins and neutron stars

    SciTech Connect (OSTI)

    Piekarewicz, J. [Department of Physics, Florida State University, Tallahassee, FL 32306-4350 (United States)

    2013-11-07T23:59:59.000Z

    The neutron-skin thickness of heavy nuclei provides a fundamental link to the equation of state of neutron-rich matter, and hence to the properties of neutron stars. The Lead Radius Experiment ('PREX') at Jefferson Laboratory has recently provided the first model-independence evidence on the existence of a neutron-rich skin in {sup 208}Pb. In this contribution we examine how the increased accuracy in the determination of neutron skins expected from the commissioning of intense polarized electron beams may impact the physics of neutron stars.

  19. The extraction of a mono-energetic neutron beam of maximum intensity from a nuclear reactor 

    E-Print Network [OSTI]

    Snow, Edward Clark

    1965-01-01T23:59:59.000Z

    of the tube at which the 40 cut was made. This plate was later to be welded into place to seal this end of the tube. A 3/4" aluminum flange to fit on the end of the beam-port was constructed from specifications supplied by the Nuclear Science Center... framework support. 19 20 10. Servo control system. 25 12. Servo control system for two rotations. Servo amplifier 26 27 LIST OF PICTURES PAGE Collimator in shielding plug. Extension tube. 7" silicon crystal in aluminum holder. Crystal, support...

  20. High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy

    E-Print Network [OSTI]

    Mor, I; Bar, D; Feldman, G; Goldberg, M B; Katz, D; Sayag, E; Shmueli, I; Cohen, Y; Tal, A; Vagish, Z; Bromberger, B; Dangendorf, V; Mugai, D; Tittelmeier, K; Weierganz, M

    2009-01-01T23:59:59.000Z

    Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several images, each at a different neutron energy (TOF). In addition, a gamma-ray image can also be simultaneously registered, allowing combined neutron/gamma inspection of objects. This permits combining the sensitivity of the fast-neutron resonance method to low-Z elements with that of gamma radiography to high-Z materials.

  1. Prognostic Utility of Cell Cycle Progression Score in Men With Prostate Cancer After Primary External Beam Radiation Therapy

    SciTech Connect (OSTI)

    Freedland, Stephen J., E-mail: steve.freedland@duke.edu [Department of Surgery, Durham VA Medical Center, Durham, North Carolina (United States); Department of Surgery (Urology), Duke University School of Medicine, Durham, North Carolina (United States); Department of Pathology, Duke University School of Medicine, Durham, North Carolina (United States); Gerber, Leah [Department of Surgery, Durham VA Medical Center, Durham, North Carolina (United States); Department of Surgery (Urology), Duke University School of Medicine, Durham, North Carolina (United States); Department of Pathology, Duke University School of Medicine, Durham, North Carolina (United States); Reid, Julia; Welbourn, William; Tikishvili, Eliso; Park, Jimmy; Younus, Adib; Gutin, Alexander; Sangale, Zaina; Lanchbury, Jerry S. [Myriad Genetics, Inc, Salt Lake City, Utah (United States); Salama, Joseph K. [Department of Radiation Oncology, Durham VA Medical Center, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University School of Medicine, Durham, North Carolina (United States); Stone, Steven [Myriad Genetics, Inc, Salt Lake City, Utah (United States)

    2013-08-01T23:59:59.000Z

    Purpose: To evaluate the prognostic utility of the cell cycle progression (CCP) score, a RNA signature based on the average expression level of 31 CCP genes, for predicting biochemical recurrence (BCR) in men with prostate cancer treated with external beam radiation therapy (EBRT) as their primary curative therapy. Methods and Materials: The CCP score was derived retrospectively from diagnostic biopsy specimens of men diagnosed with prostate cancer from 1991 to 2006 (n=141). All patients were treated with definitive EBRT; approximately half of the cohort was African American. Outcome was time from EBRT to BCR using the Phoenix definition. Median follow-up for patients without BCR was 4.8 years. Association with outcome was evaluated by Cox proportional hazards survival analysis and likelihood ratio tests. Results: Of 141 patients, 19 (13%) had BCR. The median CCP score for patient samples was 0.12. In univariable analysis, CCP score significantly predicted BCR (P=.0017). The hazard ratio for BCR was 2.55 for 1-unit increase in CCP score (equivalent to a doubling of gene expression). In a multivariable analysis that included Gleason score, prostate-specific antigen, percent positive cores, and androgen deprivation therapy, the hazard ratio for CCP changed only marginally and remained significant (P=.034), indicating that CCP provides prognostic information that is not provided by standard clinical parameters. With 10-year censoring, the CCP score was associated with prostate cancer-specific mortality (P=.013). There was no evidence for interaction between CCP and any clinical variable, including ethnicity. Conclusions: Among men treated with EBRT, the CCP score significantly predicted outcome and provided greater prognostic information than was available with clinical parameters. If validated in a larger cohort, CCP score could identify high-risk men undergoing EBRT who may need more aggressive therapy.

  2. SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3: TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    E.M. Harpenau

    2010-11-15T23:59:59.000Z

    5098-LR-02-0 SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3 TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY

  3. Neutron tubes

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Lou, Tak Pui (Berkeley, CA); Reijonen, Jani (Oakland, CA)

    2008-03-11T23:59:59.000Z

    A neutron tube or generator is based on a RF driven plasma ion source having a quartz or other chamber surrounded by an external RF antenna. A deuterium or mixed deuterium/tritium (or even just a tritium) plasma is generated in the chamber and D or D/T (or T) ions are extracted from the plasma. A neutron generating target is positioned so that the ion beam is incident thereon and loads the target. Incident ions cause D-D or D-T (or T-T) reactions which generate neutrons. Various embodiments differ primarily in size of the chamber and position and shape of the neutron generating target. Some neutron generators are small enough for implantation in the body. The target may be at the end of a catheter-like drift tube. The target may have a tapered or conical surface to increase target surface area.

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

    SciTech Connect (OSTI)

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

    2008-02-15T23:59:59.000Z

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

  5. Neutron-deuteron breakup and quasielastic scattering

    E-Print Network [OSTI]

    Ohlson, Alice Elisabeth

    2009-01-01T23:59:59.000Z

    Quasielastic scattering and deuteron breakup in the 200 MeV region is studied by impinging a pulsed neutron beam on a deuterium target at the Weapons Neutron Research facility at the Los Alamos Neutron Science Center. The ...

  6. A ROBUST ABSOLUTE DETECTION EFFICIENCY CALIBRATION METHOD UTILIZING BETA/GAMMA COINCIDENCE SIGNATURES AND ISOTOPICALLY PURIFIED NEUTRON ACTIVATED RADIOXENON ISOTOPES

    SciTech Connect (OSTI)

    McIntyre, Justin I.; Cooper, Matthew W.; Ely, James H.; Haas, Derek A.; Schrom, Brian T.

    2012-09-21T23:59:59.000Z

    Efforts to calibrate the absolute efficiency of gas cell radiations detectors have utilized a number of methodologies which allow adequate calibration but are time consuming and prone to a host of difficult-to-determine uncertainties. A method that extrapolates the total source strength from the measured beta and gamma gated beta coincidence signal was developed in the 1960’s and 1970’s. It has become clear that it is possible to achieve more consistent results across a range of isotopes and a range of activities using this method. Even more compelling is the ease with which this process can be used on routine samples to determine the total activity present in the detector. Additionally, recent advances in the generation of isotopically pure radioxenon samples of Xe-131m, Xe-133, and Xe-135 have allowed these measurement techniques to achieve much better results than would have been possible before when using mixed isotopic radioxenon source. This paper will discuss the beta/gamma absolute detection efficiency technique that utilizes several of the beta-gamma decay signatures to more precisely determine the beta and gamma efficiencies. It will than compare these results with other methods using pure sources of Xe-133, Xe-131m, and Xe-135 and a Xe-133/Xe-133m mix.

  7. am-be isotopic neutron: Topics by E-print Network

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

    of fast neutrons. Earlier studies characteristic gamma photons through inelastic scattering of an external neutron beam. These stable isotopes canNeutron Stimulated...

  8. Radiation transport analyses in support of the SNS Target Station Neutron Beam Line Shutters Title I Design

    SciTech Connect (OSTI)

    Miller, T.M.; Pevey, R.E.; Lillie, R.A.; Johnson, J.O.

    2000-12-01T23:59:59.000Z

    A detailed radiation transport analysis of the Spallation Neutron Source (SNS) shutters is important for the construction of the SNS because of its impact on conventional facility design, normal operation of the facility, and maintenance operations. Thus far the analysis of the SNS shutter travel gaps has been completed. This analysis was performed using coupled Monte Carlo and multi-dimensional discrete ordinates calculations.

  9. Advanced neutron absorber materials

    DOE Patents [OSTI]

    Branagan, Daniel J. (Idaho Falls, ID); Smolik, Galen R. (Idaho Falls, ID)

    2000-01-01T23:59:59.000Z

    A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

  10. Physics design of a cold neutron source for KIPT neutron source facility.

    SciTech Connect (OSTI)

    Zhong, Z.; Gohar, Y.; Kellogg, R.; Nuclear Engineering Division

    2009-02-17T23:59:59.000Z

    Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the conceptual design development of a neutron source facility. It is based on the use of an electron accelerator driven subcritical (ADS) facility with low enriched uranium fuel, using the existing electron accelerators at KIPT of Ukraine [1]. The neutron source of the subcritical assembly is generated from the interaction of 100-KW electron beam, which has a uniform spatial distribution and the electron energy in the range of 100 to 200 MeV, with a natural uranium target [2]. The main functions of the facility are the production of medical isotopes and the support of the Ukraine nuclear power industry. Neutron beam experiments and material studies are also included. Over the past two-three decades, structures with characteristic lengths of 100 {angstrom} and correspondingly smaller vibrational energies have become increasingly important for both science and technology [3]. The characteristic dimensions of the microstructures can be well matched by neutrons with longer vibrational wavelength and lower energy. In the accelerator-driven subcritical facility, most of the neutrons are generated from fission reactions with energy in the MeV range. They are slowed down to the meV energy range through scattering reactions in the moderator and reflector materials. However, the fraction of neutrons with energies less than 5 meV in a normal moderator spectrum is very low because of up-scattering caused by the thermal motion of moderator or reflector molecules. In order to obtain neutrons with energy less than 5 meV, cryogenically cooled moderators 'cold neutron sources' should be used to slow down the neutrons. These cold moderators shift the neutron energy spectrum down because the thermal motion of moderator molecules as well as the up-scattering is very small, which provides large gains in intensity of low energy neutrons, E < 5 meV. The accelerator driven subcritical facility is designed with a provision to add a cryogenically cooled moderator system. This cold neutron source could provide the neutrons beams with lower energy, which could be utilized in scattering experiment and material structures analysis. This study describes the performed physics analyses to define and characterize the cold neutron source of the KIPT neutron source facility. The cold neutron source is designed to optimize the cold neutron brightness to the experimental instruments outside the radial heavy concrete shield of the facility. Liquid hydrogen or solid methane with 20 K temperature is used as a cold moderator. Monte Carlo computer code MCNPX [4], with ENDF/B-VI nuclear data libraries, is utilized to calculate the cold neutron source performance and estimate the nuclear heat load to the cold moderator. The surface source generation capability of MCNPX code has been used to provide the possibility of analyzing different design configurations and perform design optimization analyses with reasonable computer resources. Several design configurations were analyzed and their performance were characterized and optimized.

  11. Probing shell structure and shape changes in neutron-rich sulfur isotopes through transient-field g factor measurements on fast radioactive beams of 38S and 40S

    E-Print Network [OSTI]

    A. D. Davies; A. E. Stuchbery; P. F. Mantica; P. M. Davidson; A. N. Wilson; A. Becerril; B. A. Brown; C. M. Campbell; J. M. Cook; D. C. Dinca; A. Gade; S. N. Liddick; T. J. Mertzimekis; W. F. Mueller; J. R. Terry; B. E. Tomlin; K. Yoneda; H. Zwahlen

    2006-02-23T23:59:59.000Z

    The shell structure underlying shape changes in neutron-rich nuclei near N=28 has been investigated by a novel application of the transient field technique to measure the first-excited state g factors in 38S and 40S produced as fast radioactive beams. There is a fine balance between proton and neutron contributions to the magnetic moments in both nuclei. The g factor of deformed 40S does not resemble that of a conventional collective nucleus because spin contributions are more important than usual.

  12. New ion-guide for the production of beams of neutron-rich nucleibetween Z = 20 - 28

    SciTech Connect (OSTI)

    Perajarvi, Kari; Cerny, Joe; Hakala, Jani; Huikari, Jussi; Jokinen, Ari; Karvonen, Pasi; Kurpeta, Jan; Lee, Dongwon; Moore, Ian; Penttila, Heikki; Popov, Andrei; Aysto, Juha

    2004-12-08T23:59:59.000Z

    It has been shown for the first time that quasi- and deep-inelastic reactions can be successfully incorporated into the conventional Ion-Guide Isotope Separator On-Line (IGISOL) technique. This is of particular interest for characterizing the decay properties of refractory elements and is applied to neutron rich nuclei between Z = 20-28. As a first step of this project, the kinematics of quasi- and deep-inelastic reactions, such as {sup 197}Au({sup 65}Cu,X)Y, were studied. Based on these studies, a specialized IGISOL target chamber was designed and built. This chamber was tested in on- and off-line conditions at the Jyvaskyla IGISOL facility. Yields of radioactive, projectile-like species such as {sup 62,63}Co are about 0.8 ions/s/pnA corresponding to a total IGISOL efficiency of about 0.06%.

  13. Pulsed-neutron monochromator

    DOE Patents [OSTI]

    Mook, Jr., Herbert A. (Oak Ridge, TN)

    1985-01-01T23:59:59.000Z

    In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The wave are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.

  14. Pulsed-neutron monochromator

    DOE Patents [OSTI]

    Mook, H.A. Jr.

    1984-01-01T23:59:59.000Z

    In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The waves are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.

  15. Fast neutron imaging device and method

    DOE Patents [OSTI]

    Popov, Vladimir; Degtiarenko, Pavel; Musatov, Igor V.

    2014-02-11T23:59:59.000Z

    A fast neutron imaging apparatus and method of constructing fast neutron radiography images, the apparatus including a neutron source and a detector that provides event-by-event acquisition of position and energy deposition, and optionally timing and pulse shape for each individual neutron event detected by the detector. The method for constructing fast neutron radiography images utilizes the apparatus of the invention.

  16. Proton recoil scintillator neutron rem meter

    DOE Patents [OSTI]

    Olsher, Richard H. (Los Alamos, NM); Seagraves, David T. (Los Alamos, NM)

    2003-01-01T23:59:59.000Z

    A neutron rem meter utilizing proton recoil and thermal neutron scintillators to provide neutron detection and dose measurement. In using both fast scintillators and a thermal neutron scintillator the meter provides a wide range of sensitivity, uniform directional response, and uniform dose response. The scintillators output light to a photomultiplier tube that produces an electrical signal to an external neutron counter.

  17. Neutron capture therapies

    DOE Patents [OSTI]

    Yanch, Jacquelyn C. (Cambridge, MA); Shefer, Ruth E. (Newton, MA); Klinkowstein, Robert E. (Winchester, MA)

    1999-01-01T23:59:59.000Z

    In one embodiment there is provided an application of the .sup.10 B(n,.alpha.).sup.7 Li nuclear reaction or other neutron capture reactions for the treatment of rheumatoid arthritis. This application, called Boron Neutron Capture Synovectomy (BNCS), requires substantially altered demands on neutron beam design than for instance treatment of deep seated tumors. Considerations for neutron beam design for the treatment of arthritic joints via BNCS are provided for, and comparisons with the design requirements for Boron Neutron Capture Therapy (BNCT) of tumors are made. In addition, exemplary moderator/reflector assemblies are provided which produce intense, high-quality neutron beams based on (p,n) accelerator-based reactions. In another embodiment there is provided the use of deuteron-based charged particle reactions to be used as sources for epithermal or thermal neutron beams for neutron capture therapies. Many d,n reactions (e.g. using deuterium, tritium or beryllium targets) are very prolific at relatively low deuteron energies.

  18. Spallation-neutron sources

    SciTech Connect (OSTI)

    Michaudon, A.

    1997-09-01T23:59:59.000Z

    Of particular interest for neutron-physics studies are spallation-neutron sources (SNSs) using intense proton beams with energies in the GeV range. Some SNSs already provide average fluxes of thermal and cold neutrons comparable with those of high-flux reactors. Most SNSs are pulsed with high peak fluxes that can be used with the powerful time-of-flight (TOF) method. Also, SNSs could be developed to much higher performance.

  19. Development of a compact in situ polarized {sup 3}He neutron spin filter at Oak Ridge National Laboratory

    SciTech Connect (OSTI)

    Jiang, C. Y.; Tong, X., E-mail: tongx@ornl.gov; Brown, D. R.; Kadron, B. J.; Robertson, J. L. [Instrument and Source Design Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Chi, S.; Christianson, A. D.; Winn, B. L. [Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-07-15T23:59:59.000Z

    We constructed a compact in situ polarized {sup 3}He neutron spin filter based on spin-exchange optical pumping which is capable of continuous pumping of the {sup 3}He gas while the system is in place in the neutron beam on an instrument. The compact size and light weight of the system simplifies its utilization on various neutron instruments. The system has been successfully tested as a neutron polarizer on the triple-axis spectrometer (HB3) and the hybrid spectrometer (HYSPEC) at Oak Ridge National Laboratory. Over 70% {sup 3}He polarization was achieved and maintained during the test experiments. Over 90% neutron polarization and an average of 25% transmission for neutrons of 14.7 meV and 15 meV was also obtained.

  20. The early development of neutron diffraction: Science in the wings of the Manhattan Project

    SciTech Connect (OSTI)

    Mason, Thom [ORNL] [ORNL; Gawne, Timothy J [ORNL] [ORNL; Nagler, Stephen E [ORNL] [ORNL; Nestor, Margaret Boone {Bonnie} [ORNL; Carpenter, John M [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    Although neutron diffraction was first observed using radioactive decay sources shortly after the discovery of the neutron, it was only with the availability of higher intensity neutron beams from the first nuclear reactors, constructed as part of the Manhattan project, that systematic investigation of Bragg scattering became possible. Remarkably, at a time when the war effort was singularly focused on the development of the atomic bomb, groups working at Oak Ridge and Chicago carried out key measurements and recognized the future utility of neutron diffraction quite independent of its contributions to the measurements of nuclear cross sections. Ernest O. Wollan, Lyle B. Borst, and Walter H. Zinn were all able to observe neutron diffraction in 1944 using the X-10 graphite reactor and the CP-3 heavy water reactor.

  1. axisymmetric electron beam: Topics by E-print Network

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

    dominated beams F. Filbet 1 , J.-L. Lemaire Filbet, Francis 2 From x-ray telescopes to neutron scattering: using axisymmetric mirrors to focus a neutron beam CERN Preprints...

  2. Neutron Imaging of Diesel Particulate Filters

    Broader source: Energy.gov (indexed) [DOE]

    August 3 2009 Non-invasive, non-destructive technique based on attenuation of the neutron beam. Neutrons interact with nuclei and their scattering power does not vary in...

  3. Neutron-deuteron breakup reaction as a tool for studying neutron-neutron interactions

    SciTech Connect (OSTI)

    Konobeevski, E. S., E-mail: konobeev@inr.ru; Zuyev, S. V.; Mordovskoy, M. V.; Potashev, S. I.; Sharapov, I. M. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)] [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

    2013-11-15T23:59:59.000Z

    An analysis of the most recent data on the reaction nd {yields} pnn revealed a serious discrepancy between theoretical predictions and cross sections measured for this reaction in various configurations where the role of neutron-neutron interactions is important. In view of this, it seems necessary both to develop theoretical approaches and to obtain new experimental data. For this purpose, a setup for studying the neutron-deuteron breakup reaction was created at the Institute for Nuclear Research on the basis of the neutron beam in the RADEX channel and deuterium targets. This facility makes it possible to perform experiments over a broad region of primary-neutron energies (10-60 MeV) and in various (final-state interaction, quasifree scattering, and spatial-star) configurations. Preliminary results of the respective experiment were obtained for configurations of final-state neutron-neutron interaction and quasifree neutron-neutron scattering.

  4. SINGLE CRYSTAL NEUTRON DIFFRACTION.

    SciTech Connect (OSTI)

    KOETZLE,T.F.

    2001-03-13T23:59:59.000Z

    Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for information on magnetic scattering of neutrons see Unit 14.3. Instruments for single-crystal diffraction (single-crystal diffractometers or SCDs) are generally available at the major neutron scattering center facilities. Beam time on many of these instruments is available through a proposal mechanism. A listing of neutron SCD instruments and their corresponding facility contacts is included in an appendix accompanying this unit.

  5. Scattered neutron tomography based on a neutron transport problem 

    E-Print Network [OSTI]

    Scipolo, Vittorio

    2005-11-01T23:59:59.000Z

    scattering objects because it does not adequately account for the scattering component of the neutron beam intensity exiting the sample. We proposed a new method of computed tomography which employs an inverse problem analysis of both the transmitted...

  6. Scattered neutron tomography based on a neutron transport problem

    E-Print Network [OSTI]

    Scipolo, Vittorio

    2005-11-01T23:59:59.000Z

    scattering objects because it does not adequately account for the scattering component of the neutron beam intensity exiting the sample. We proposed a new method of computed tomography which employs an inverse problem analysis of both the transmitted...

  7. Nuclear analysis of integral experiments on a Li{sub 2}O test assembly with local heterogeneities utilizing a 14-MeV neutron source

    SciTech Connect (OSTI)

    Youssef, M.Z.; Kumar, A.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States)] [and others

    1995-09-01T23:59:59.000Z

    The integral experiments and postanalyses performed in Phase IIC of the U.S. Department of Energy (U.S. DOE)/Japan Atomic Energy Research Institute (JAERI) collaborative program on fusion neutronics focused on rest blankets that include the actual heterogeneities found in several blanket designs. In one arrangement, multi-layers of Li{sub 2}O and beryllium were placed in an edge-on, horizontally alternating configuration, and in the second arrangement, vertical water coolant channels were deployed. The main objective has been to examine the accuracy of predicting key parameters such as tritium production rate (TPR), in-system spectrum, and other reaction rates around these heterogeneities and to experimentally verify the enhancement in TPR by beryllium in the first experiment. The prediction accuracy was examined in terms of calculated-to-experimental values (c/e){sub i} of the neutronics parameters at several spatial locations. Average local (c/e){sub i} values were statistically calculated for TPR from Li-6 (T{sub 6}) and from Li-7 (T{sub 7}) in addition to quantifying the prediction uncertainties in the line-integrated TPR. A relationship was developed between the prediction uncertainty in the integrated TPR and the corresponding values in the total breeding zone. This relationship enabled us to identify which subzone contributes the most to the prediction uncertainty in the overall integrated TPR. 39 refs., 23 figs., 13 tabs.

  8. Wire Scanner Beam Profile Measurements: LANSCE Facility Beam Development

    SciTech Connect (OSTI)

    Gilpatrick, John D. [Los Alamos National Laboratory; Batygin, Yuri K. [Los Alamos National Laboratory; Gonzales, Fermin [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Kutac, Vincent G. [Los Alamos National Laboratory; Martinez, Derwin [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

    2012-05-15T23:59:59.000Z

    The Los Alamos Neutron Science Center (LANSCE) is replacing Wire Scanner (WS) beam profile measurement systems. Three beam development tests have taken place to test the new wire scanners under beam conditions. These beam development tests have integrated the WS actuator, cable plant, electronics processors and associated software and have used H{sup -} beams of different beam energy and current conditions. In addition, the WS measurement-system beam tests verified actuator control systems for minimum profile bin repeatability and speed, checked for actuator backlash and positional stability, tested the replacement of simple broadband potentiometers with narrow band resolvers, and tested resolver use with National Instruments Compact Reconfigurable Input and Output (cRIO) Virtual Instrumentation. These beam tests also have verified how trans-impedance amplifiers react with various types of beam line background noise and how noise currents were not generated. This paper will describe these beam development tests and show some resulting data.

  9. Utility Partnerships

    Broader source: Energy.gov [DOE]

    Utility Partnerships 7/10/12. Provides an overview of LEAP's (Charlottesville, VA) partnership with local utilities.

  10. 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]

    D. Habs; P. G. Thirolf; M. Gross; K. Allinger; J. Bin; A. Henig; D. Kiefer; W. Ma; J. Schreiber

    2010-09-10T23:59:59.000Z

    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.

  11. Pulsed neutron detector

    DOE Patents [OSTI]

    Robertson, deceased, J. Craig (late of Albuquerque, NM); Rowland, Mark S. (Livermore, CA)

    1989-03-21T23:59:59.000Z

    A pulsed neutron detector and system for detecting low intensity fast neutron pulses has a body of beryllium adjacent a body of hydrogenous material the latter of which acts as a beta particle detector, scintillator, and moderator. The fast neutrons (defined as having En>1.5 MeV) react in the beryllium and the hydrogenous material to produce larger numbers of slow neutrons than would be generated in the beryllium itself and which in the beryllium generate hellium-6 which decays and yields beta particles. The beta particles reach the hydrogenous material which scintillates to yield light of intensity related to the number of fast neutrons. A photomultiplier adjacent the hydrogenous material (scintillator) senses the light emission from the scintillator. Utilization means, such as a summing device, sums the pulses from the photo-multiplier for monitoring or other purposes.

  12. Previously, DC Magnets located at Neutron-Scattering Beamlines were commercially-manufactured superconducting magnets and limited to 17 T. A

    E-Print Network [OSTI]

    Weston, Ken

    Previously, DC Magnets located at Neutron-Scattering Beamlines were commercially, this was the first designed specifically for neutron scattering and the first to include resistive suitable for neutron scattering, diffraction and spectroscopy experiments with the neutron beam passing

  13. Compact neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Lou, Tak Pui

    2005-03-22T23:59:59.000Z

    A compact neutron generator has at its outer circumference a toroidal shaped plasma chamber in which a tritium (or other) plasma is generated. A RF antenna is wrapped around the plasma chamber. A plurality of tritium ion beamlets are extracted through spaced extraction apertures of a plasma electrode on the inner surface of the toroidal plasma chamber and directed inwardly toward the center of neutron generator. The beamlets pass through spaced acceleration and focusing electrodes to a neutron generating target at the center of neutron generator. The target is typically made of titanium tubing. Water is flowed through the tubing for cooling. The beam can be pulsed rapidly to achieve ultrashort neutron bursts. The target may be moved rapidly up and down so that the average power deposited on the surface of the target may be kept at a reasonable level. The neutron generator can produce fast neutrons from a T-T reaction which can be used for luggage and cargo interrogation applications. A luggage or cargo inspection system has a pulsed T-T neutron generator or source at the center, surrounded by associated gamma detectors and other components for identifying explosives or other contraband.

  14. Neutron Generators Developed at LBNL for Homeland Security and Imaging Applications

    E-Print Network [OSTI]

    Reijonen, Jani

    2006-01-01T23:59:59.000Z

    GENERATORS DEVELOPED AT LBNL FOR HOMELAND SECURITY ANDdifference between the LBNL neutron generators in comparisonmethod utilized in the LBNL neutron generators is based on

  15. Cyclotron-based neutron source for BNCT

    SciTech Connect (OSTI)

    Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Ogasawara, T.; Fujita, K. [Sumitomo Heavy Industries, Ltd (Japan); Tanaka, H.; Sakurai, Y.; Maruhashi, A. [Kyoto University Research Reactor Institute (Japan)

    2013-04-19T23:59:59.000Z

    Kyoto University Research Reactor Institute (KURRI) and Sumitomo Heavy Industries, Ltd. (SHI) have developed a cyclotron-based neutron source for Boron Neutron Capture Therapy (BNCT). It was installed at KURRI in Osaka prefecture. The neutron source consists of a proton cyclotron named HM-30, a beam transport system and an irradiation and treatment system. In the cyclotron, H- ions are accelerated and extracted as 30 MeV proton beams of 1 mA. The proton beams is transported to the neutron production target made by a beryllium plate. Emitted neutrons are moderated by lead, iron, aluminum and calcium fluoride. The aperture diameter of neutron collimator is in the range from 100 mm to 250 mm. The peak neutron flux in the water phantom is 1.8 Multiplication-Sign 109 neutrons/cm{sup 2}/sec at 20 mm from the surface at 1 mA proton beam. The neutron source have been stably operated for 3 years with 30 kW proton beam. Various pre-clinical tests including animal tests have been done by using the cyclotron-based neutron source with {sup 10}B-p-Borono-phenylalanine. Clinical trials of malignant brain tumors will be started in this year.

  16. Neutronic reactor

    DOE Patents [OSTI]

    Wende, Charles W. J. (Augusta, GA); Babcock, Dale F. (Wilmington, DE); Menegus, Robert L. (Wilmington, DE)

    1983-01-01T23:59:59.000Z

    A nuclear reactor includes an active portion with fissionable fuel and neutron moderating material surrounded by neutron reflecting material. A control element in the active portion includes a group of movable rods constructed of neutron-absorbing material. Each rod is movable with respect to the other rods to vary the absorption of neutrons and effect control over neutron flux.

  17. aerial neutron detection: Topics by E-print Network

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

    (clutter) using neutron beams from Cf-252 (more) Johll, Mark 2009-01-01 50 An aerogel Cherenkov detector for multi-GeV photon detection with low sensitivity to neutrons...

  18. Nuclear Instruments and Methods in Physics Research A 562 (2006) 401406 Generating a multi-line neutron beam using an electron

    E-Print Network [OSTI]

    Danon, Yaron

    Polytechnic Institute, Troy, New York 12180, USA Received 3 January 2006; received in revised form 20 February discrete energy lines in the range 34­6200 eV is produced by using a 238 U filter in conjunction beams of discrete energies can be generated by using an electron linear accelerator in combination

  19. Portable neutron spectrometer and dosimeter

    DOE Patents [OSTI]

    Waechter, David A. (Los Alamos, NM); Erkkila, Bruce H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM)

    1985-01-01T23:59:59.000Z

    The disclosure relates to a battery operated neutron spectrometer/dosimeter utilizing a microprocessor, a built-in tissue equivalent LET neutron detector, and a 128-channel pulse height analyzer with integral liquid crystal display. The apparatus calculates doses and dose rates from neutrons incident on the detector and displays a spectrum of rad or rem as a function of keV per micron of equivalent tissue and also calculates and displays accumulated dose in millirads and millirem as well as neutron dose rates in millirads per hour and millirem per hour.

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

    SciTech Connect (OSTI)

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

    2000-06-28T23:59:59.000Z

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

  1. Mechanical approach to the neutrons spectra collimation and detection

    SciTech Connect (OSTI)

    Sadeghi, H.; Roshan, M. V. [Energy Engineering and Physics Department, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2014-11-15T23:59:59.000Z

    Neutrons spectra from most of known sources require being collimated for numerous applications; among them one is the Neutron Activation Analysis. High energy neutrons are collimated through a mechanical procedure as one of the most promising methods. The output energy of the neutron beam depends on the velocity of the rotating Polyethylene disks. The collimated neutrons are then measured by an innovative detection technique with high accuracy.

  2. Transverse beam shape measurements of intense proton beams using optical transition radiation

    SciTech Connect (OSTI)

    Scarpine, Victor E.; /Fermilab

    2012-03-01T23:59:59.000Z

    A number of particle physics experiments are being proposed as part of the Department of Energy HEP Intensity Frontier. Many of these experiments will utilize megawatt level proton beams onto targets to form secondary beams of muons, kaons and neutrinos. These experiments require transverse size measurements of the incident proton beam onto target for each beam spill. Because of the high power levels, most beam intercepting profiling techniques will not work at full beam intensity. The possibility of utilizing optical transition radiation (OTR) for high intensity proton beam profiling is discussed. In addition, previous measurements of OTR beam profiles from the NuMI beamline are presented.

  3. Applicability of a Bonner Shere technique for pulsed neutron in 120 GeV proton facility

    SciTech Connect (OSTI)

    Sanami, T.; Hagiwara, M.; Iwase, H.; /KEK, Tsukuba; Iwamoto, Y.; Sakamoto, Y.; Nakashima, H.; /JAEA, Ibaraki; Arakawa, H.; Shigyo, N.; /Kyushu U.; Leveling, A.F.; Boehnlein, D.J.; Vaziri, K.; /Fermilab

    2008-02-01T23:59:59.000Z

    The data on neutron spectra and intensity behind shielding are important for radiation safety design of high-energy accelerators since neutrons are capable of penetrating thick shielding and activating materials. Corresponding particle transport codes--that involve physics models of neutron and other particle production, transportation, and interaction--have been developed and used world-wide [1-8]. The results of these codes have been ensured through plenty of comparisons with experimental results taken in simple geometries. For neutron generation and transport, several related experiments have been performed to measure neutron spectra, attenuation length and reaction rates behind shielding walls of various thicknesses and materials in energy range up to several hundred of MeV [9-11]. The data have been used to benchmark--and modify if needed--the simulation modes and parameters in the codes, as well as the reference data for radiation safety design. To obtain such kind of data above several hundred of MeV, Japan-Fermi National Accelerator Laboratory (FNAL) collaboration for shielding experiments has been started in 2007, based on suggestion from the specialist meeting of shielding, Shielding Aspects of Target, Irradiation Facilities (SATIF), because of very limited data available in high-energy region (see, for example, [12]). As a part of this shielding experiment, a set of Bonner sphere (BS) was tested at the antiproton production target facility (pbar target station) at FNAL to obtain neutron spectra induced by a 120-GeV proton beam in concrete and iron shielding. Generally, utilization of an active detector around high-energy accelerators requires an improvement on its readout to overcome burst of secondary radiation since the accelerator delivers an intense beam to a target in a short period after relatively long acceleration period. In this paper, we employ BS for a spectrum measurement of neutrons that penetrate the shielding wall of the pbar target station in FNAL.

  4. Computer simulation of neutron capture therapy.

    E-Print Network [OSTI]

    Olson, Arne Peter

    1967-01-01T23:59:59.000Z

    Analytical methods are developed to simulate on a large digital computer the production and use of reactor neutron beams f or boron capture therapy of brain tumors. The simulation accounts for radiation dose distributions ...

  5. Computer simulation of neutron capture therapy

    E-Print Network [OSTI]

    Olson, Arne Peter

    1967-01-01T23:59:59.000Z

    Analytical methods are developed to simulate on a large digital computer the production and use of reactor neutron beams f or boron capture therapy of brain tumors. The simulation accounts for radiation dose distributions ...

  6. Time-resolved neutron imaging at ANTARES cold neutron beamline

    E-Print Network [OSTI]

    Tremsin, A S; Tittelmeier, K; Schillinger, B; Schulz, M; Lerche, M; Feller, W B

    2015-01-01T23:59:59.000Z

    In non-destructive evaluation with X-rays light elements embedded in dense, heavy (or high-Z) matrices show little contrast and their structural details can hardly be revealed. Neutron radiography, on the other hand, provides a solution for those cases, in particular for hydrogenous materials, owing to the large neutron scattering cross section of hydrogen and uncorrelated dependency of neutron cross section on the atomic number. The majority of neutron imaging experiments at the present time is conducted with static objects mainly due to the limited flux intensity of neutron beamline facilities and sometimes due to the limitations of the detectors. However, some applications require the studies of dynamic phenomena and can now be conducted at several high intensity beamlines such as the recently rebuilt ANTARES beam line at the FRM-II reactor. In this paper we demonstrate the capabilities of time resolved imaging for repetitive processes, where different phases of the process can be imaged simultaneously and...

  7. CHINA SPALLATION NEUTRON SOURCE DESIGN.

    SciTech Connect (OSTI)

    WEI,J.

    2007-01-29T23:59:59.000Z

    The China Spallation Neutron Source (CSNS) is an accelerator-based high-power project currently in preparation under the direction of the Chinese Academy of Sciences (CAS). The complex is based on an H- linear accelerator, a rapid cycling proton synchrotron accelerating the beam to 1.6 GeV, a solid tungsten target station, and five initial instruments for spallation neutron applications. The facility will operate at 25 Hz repetition rate with a phase-I beam power of about 120 kW. The major challenge is to build a robust and reliable user's facility with upgrade potential at a fractional of ''world standard'' cost.

  8. Neutron Diffraction and Optics of a Noncentrosymmetric Crystal. New Feasibility of a Search for Neutron EDM

    E-Print Network [OSTI]

    V. V. Fedorov; V. V. Voronin

    2005-05-03T23:59:59.000Z

    Recently strong electric fields (up to 10^9 V/cm) have been discovered, which affect the neutrons moving in noncentrosymmetric crystals. Such fields allow new polarization phenomena in neutron diffraction and optics and provide, for instance, a new feasibility of a search for the neutron electric dipole moment (EDM). A series of experiments was carried out in a few last years on study of the dynamical diffraction of polarized neutrons in thick (1-10 cm) quartz crystals, using the forward diffraction beam and Bragg angles close to 90^0. As well new neutron optics phenomena were investigated. The feasibility of experiment on a search for neutron EDM using Laue diffraction in crystals without a center of symmetry was tested at the reactors: WWR-M in Gatchina and HFR in Grenoble. It was shown that the sensitivity can reach (3 - 6)\\cdot 10^{-25}e cm per day for the available quartz crystal and cold neutron beam flux.

  9. Computational characterization and experimental validation of the thermal neutron source for neutron capture therapy research at the University of Missouri

    SciTech Connect (OSTI)

    Broekman, J. D. [University of Missouri, Research Reactor Center, 1513 Research Park Drive, Columbia, MO 65211-3400 (United States); Nigg, D. W. [Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83415 (United States); Hawthorne, M. F. [University of Missouri, International Institute of Nano and Molecular Medicine, 1514 Research Park Dr., Columbia, MO 65211-3450 (United States)

    2013-07-01T23:59:59.000Z

    Parameter studies, design calculations and neutronic performance measurements have been completed for a new thermal neutron beamline constructed for neutron capture therapy cell and small-animal radiobiology studies at the University of Missouri Research Reactor. The beamline features the use of single-crystal silicon and bismuth sections for neutron filtering and for reduction of incident gamma radiation. The computational models used for the final beam design and performance evaluation are based on coupled discrete-ordinates and Monte Carlo techniques that permit detailed modeling of the neutron transmission properties of the filtering crystals with very few approximations. Validation protocols based on neutron activation spectrometry measurements and rigorous least-square adjustment techniques show that the beam produces a neutron spectrum that has the anticipated level of thermal neutron flux and a somewhat higher than expected, but radio-biologically insignificant, epithermal neutron flux component. (authors)

  10. Neutron guide

    DOE Patents [OSTI]

    Greene, Geoffrey L. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    A neutron guide in which lengths of cylindrical glass tubing have rectangular glass plates properly dimensioned to allow insertion into the cylindrical glass tubing so that a sealed geometrically precise polygonal cross-section is formed in the cylindrical glass tubing. The neutron guide provides easier alignment between adjacent sections than do the neutron guides of the prior art.

  11. Quantitative imaging of freezing at the millimeter scale using neutron radiography

    E-Print Network [OSTI]

    Deinert, Mark

    is capable of 1.1 MW steady state power. The thermal neutron imaging facility is located on a tangential to stay below regulatory limits. The beam port flux increases proportionally with reactor power neutron beam port in which the thermal neutron flux at 500 kW steady state operation has been previously

  12. Secondary neutrons in clinical proton radiotherapy: A charged issue

    E-Print Network [OSTI]

    Brenner, David Jonathan

    -body neutron dose, due to interactions of the protons with the scattering and collimating beam elements radiotherapy; Secondary neutrons; Second cancers; Passive scattering The development of hospital-based proton on establishing the neutron doses involved [7­20], there is still no agree- ment about whether these scattered

  13. Neutron Stimulated Emission Computed Tomography of Stable Isotopes

    E-Print Network [OSTI]

    on the development of a new molecular imaging technique using inelastic scattering of fast neutrons. Earlier studies characteristic gamma photons through inelastic scattering of an external neutron beam. These stable isotopes canNeutron Stimulated Emission Computed Tomography of Stable Isotopes Carey E. Floyd Jr.*ab , Calvin

  14. SANS -Small Angle Neutron Scattering Tcnica de difrao

    E-Print Network [OSTI]

    Loh, Watson

    SANS - Small Angle Neutron Scattering Técnica de difração informações sobre tamanho e forma de- Neutrons are created in the centre of the target station when the beam of high energy protons collides by evaporating nuclear particles, mainly neutrons, in all directions. Each proton produces approximately 15

  15. A Java-based Science Portal for Neutron Scattering Experiments

    E-Print Network [OSTI]

    Vazhkudai, Sudharshan

    A Java-based Science Portal for Neutron Scattering Experiments Sudharshan S. Vazhkudai James A scattering facility recently commissioned by the US Department of Energy (DOE). The neutron beam produced (SNS) [14] is a large-scale leading- edge neutron scattering facility that hopes to fundamen- tally

  16. Nuclear astrophysics and electron beams

    SciTech Connect (OSTI)

    Schwenk, A. [Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany)

    2013-11-07T23:59:59.000Z

    Electron beams provide important probes and constraints for nuclear astrophysics. This is especially exciting at energies within the regime of chiral effective field theory (EFT), which provides a systematic expansion for nuclear forces and electroweak operators based on quantum chromodynamics. This talk discusses some recent highlights and future directions based on chiral EFT, including nuclear structure and reactions for astrophysics, the neutron skin and constraints for the properties of neutron-rich matter in neutron stars and core-collapse supernovae, and the dark matter response of nuclei.

  17. Neutron producing target for accelerator based neutron source for

    E-Print Network [OSTI]

    Taskaev, Sergey Yur'evich

    therapy [1, 2]. Lithium targets for two modes of neutron beam production are developed. The first one. Target will be created as a 2 ­ 3 µm thick lithium layer on the surface of tungsten disk cooled by liquidW cm­2 . ii) Production of target with lithium layer thickness of 2 ­ 3 µm. #12;248 iii) Evaporation

  18. Facility for fast neutron irradiation tests of electronics at the ISIS spallation neutron source

    SciTech Connect (OSTI)

    Andreani, C.; Pietropaolo, A.; Salsano, A. [Centro NAST, Universita degli Studi di Roma Tor Vergata (Italy); Gorini, G.; Tardocchi, M. [Dipartimento di Fisica 'G. Occhialini', Universita degli Studi di Milano-Bicocca (Italy); Paccagnella, A.; Gerardin, S. [Dipartimento di Ingegneria dell'Informazione, Universita di Padova (Italy); Frost, C. D.; Ansell, S. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Platt, S. P. [School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Preston, Lancs. PR1 2HE (United Kingdom)

    2008-03-17T23:59:59.000Z

    The VESUVIO beam line at the ISIS spallation neutron source was set up for neutron irradiation tests in the neutron energy range above 10 MeV. The neutron flux and energy spectrum were shown, in benchmark activation measurements, to provide a neutron spectrum similar to the ambient one at sea level, but with an enhancement in intensity of a factor of 10{sup 7}. Such conditions are suitable for accelerated testing of electronic components, as was demonstrated here by measurements of soft error rates in recent technology field programable gate arrays.

  19. Neutron sources: Present practice and future potential

    SciTech Connect (OSTI)

    Cierjacks, S.; Smith, A.B.

    1988-01-01T23:59:59.000Z

    The present capability and future potential of accelerator-based monoenergetic and white neutron sources are outlined in the context of fundamental and applied neutron-nuclear research. The neutron energy range extends from thermal to 500 MeV, and the time domain from steady-state to pico-second pulsed sources. Accelerator technology is summarized, including the production of intense light-ion, heavy-ion and electron beams. Target capabilities are discussed with attention to neutron-producing efficiency and power-handling capabilities. The status of underlying neutron-producing reactions is summarized. The present and future use of neutron sources in: fundamental neutron-nuclear research, nuclear data acquisition, materials damage studies, engineering tests, and biomedical applications are discussed. Emphasis is given to current status, near-term advances well within current technology, and to long-range projections. 90 refs., 4 figs.

  20. Measurement of delayed-neutron yield from {sup 237}Np fission induced by thermal neutrons

    SciTech Connect (OSTI)

    Gundorin, N. A.; Zhdanova, K. V.; Zhuchko, V. E.; Pikelner, L. B., E-mail: plb@nf.jinr.ru; Rebrova, N. V.; Salamatin, I. M.; Smirnov, V. I.; Furman, V. I. [Joint Institute for Nuclear Research (Russian Federation)

    2007-06-15T23:59:59.000Z

    The delayed-neutron yield from thermal-neutron-induced fission of the {sup 237}Np nucleus was measured using a sample periodically exposed to a pulsed neutron beam with subsequent detection of neutrons during the time intervals between pulses. The experiment was realized on an Isomer-M setup mounted in the IBR-2 pulsed reactor channel equipped with a mirror neutron guide. The setup and the experimental procedure are described, the background sources are thoroughly analyzed, and the experimental data are presented. The total delayed-neutron yield from {sup 237}Np fission induced by thermal neutrons is {nu}{sub d} = 0.0110 {+-} 0.0009. This study was performed at the Frank Laboratory of Neutron Physics (JINR, Dubna)

  1. Asterix is a reflectometer/diffractometer/grazing-incidence-SANS/SESAME-enabled-SANS spectrometer that is primarily used for experiments or neutron scattering

    E-Print Network [OSTI]

    that is primarily used for experiments or neutron scattering techniques requiring polarized neutron beams detector arm is readily configurable for polarization or energy analysis of the scattered neutron beam be translated in the horizontal and vertical directions. Neutron detector (Spin Echo Scattering Angle

  2. Instrumentation for Neutron Scattering at the Missouri University Research Reactor Paul F. Miceli

    E-Print Network [OSTI]

    Montfrooij, Wouter

    Instrumentation for Neutron Scattering at the Missouri University Research Reactor Paul F. Miceli Research Reactor (MURR) provides significant thermal neutron flux, which enables neutron scattering]. There are presently 5 instruments located on the beam port floor that are dedicated to neutron scattering: (1) TRIAX

  3. Neutron Scattering Tutorials | Neutron Science | ORNL

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

    Neutron Scattering Tutorials SHARE Neutron Scattering Tutorials The following lectures were presented at the 2011 and 2010 National School on Neutron & X-Ray Scattering. This...

  4. Neutron detector

    DOE Patents [OSTI]

    Stephan, Andrew C. (Knoxville, TN); Jardret; Vincent D. (Powell, TN)

    2011-04-05T23:59:59.000Z

    A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

  5. Accelerator-based neutron source for boron neutron capture therapy (BNCT) and method

    DOE Patents [OSTI]

    Yoon, W.Y.; Jones, J.L.; Nigg, D.W.; Harker, Y.D.

    1999-05-11T23:59:59.000Z

    A source for boron neutron capture therapy (BNCT) comprises a body of photoneutron emitter that includes heavy water and is closely surrounded in heat-imparting relationship by target material; one or more electron linear accelerators for supplying electron radiation having energy of substantially 2 to 10 MeV and for impinging such radiation on the target material, whereby photoneutrons are produced and heat is absorbed from the target material by the body of photoneutron emitter. The heavy water is circulated through a cooling arrangement to remove heat. A tank, desirably cylindrical or spherical, contains the heavy water, and a desired number of the electron accelerators circumferentially surround the tank and the target material as preferably made up of thin plates of metallic tungsten. Neutrons generated within the tank are passed through a surrounding region containing neutron filtering and moderating materials and through neutron delimiting structure to produce a beam or beams of epithermal neutrons normally having a minimum flux intensity level of 1.0{times}10{sup 9} neutrons per square centimeter per second. Such beam or beams of epithermal neutrons are passed through gamma ray attenuating material to provide the required epithermal neutrons for BNCT use. 3 figs.

  6. Accelerator-based neutron source for boron neutron capture therapy (BNCT) and method

    DOE Patents [OSTI]

    Yoon, Woo Y. (Idaho Falls, ID); Jones, James L. (Idaho Falls, ID); Nigg, David W. (Idaho Falls, ID); Harker, Yale D. (Idaho Falls, ID)

    1999-01-01T23:59:59.000Z

    A source for boron neutron capture therapy (BNCT) comprises a body of photoneutron emitter that includes heavy water and is closely surrounded in heat-imparting relationship by target material; one or more electron linear accelerators for supplying electron radiation having energy of substantially 2 to 10 MeV and for impinging such radiation on the target material, whereby photoneutrons are produced and heat is absorbed from the target material by the body of photoneutron emitter. The heavy water is circulated through a cooling arrangement to remove heat. A tank, desirably cylindrical or spherical, contains the heavy water, and a desired number of the electron accelerators circumferentially surround the tank and the target material as preferably made up of thin plates of metallic tungsten. Neutrons generated within the tank are passed through a surrounding region containing neutron filtering and moderating materials and through neutron delimiting structure to produce a beam or beams of epithermal neutrons normally having a minimum flux intensity level of 1.0.times.10.sup.9 neutrons per square centimeter per second. Such beam or beams of epithermal neutrons are passed through gamma ray attenuating material to provide the required epithermal neutrons for BNCT use.

  7. Fourteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Fourteenth National School on Neutron and X-ray Scattering August 12 - 25, 2012 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

  8. Tenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Tenth National School on Neutron and X-ray Scattering September 24 - October 11, 2008 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  9. National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    15th National School on Neutron and X-ray Scattering August 10 - 24, 2013 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

  10. Thirteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Thirteenth National School on Neutron and X-ray Scattering June 11 ­ June 25, 2011 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  11. Sixteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Sixteenth National School on Neutron and X-ray Scattering June 14-28, 2014 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major's Neutron Scattering Science Division. Scientific Directors: Suzanne G.E. te Velthuis, Esen Ercan Alp

  12. Twelfth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Twelfth National School on Neutron and X-ray Scattering June 12 ­ June 26, 2010 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  13. National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    National School on Neutron and X-ray Scattering May 30 ­ June 13, 2009 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  14. Neutron tube design study for boron neutron capture therapy application

    SciTech Connect (OSTI)

    Verbeke, J.M.; Lee, Y.; Leung, K.N.; Vujic, J.; Williams, M.D.; Wu, L.K.; Zahir, N.

    1999-05-06T23:59:59.000Z

    Radio-frequency (RF) driven ion sources are being developed in Lawrence Berkeley National Laboratory (LBNL) for sealed-accelerator-tube neutron generator application. By using a 5-cm-diameter RF-driven multicusp source H{sup +} yields over 95% have been achieved. These experimental findings will enable one to develop compact neutron generators based on the D-D or D-T fusion reactions. In this new neutron generator, the ion source, the accelerator and the target are all housed in a sealed metal container without external pumping. Recent moderator design simulation studies have shown that 14 MeV neutrons could be moderated to therapeutically useful energy ranges for boron neutron capture therapy (BNCT). The dose near the center of the brain with optimized moderators is about 65% higher than the dose obtained from a typical neutron spectrum produced by the Brookhaven Medical Research Reactor (BMRR), and is comparable to the dose obtained by other accelerator-based neutron sources. With a 120 keV and 1 A deuteron beam, a treatment time of {approx}35 minutes is estimated for BNCT.

  15. Synthesize Neutron-Drip-Line-Nuclides with Free-Neutron Bose-Einstein Condensates Experimentally

    E-Print Network [OSTI]

    Bao-Guo Dong

    2014-09-22T23:59:59.000Z

    We first show a possible way to create a new type of matter, free-neutron Bose-Einstein condensate by the ultracold free-neutron-pair Bose-Einstein condensation and then determine the neutron drip line experimentally. The Bose-Einstein condensation of bosonic and fermionic atoms in atomic gases was performed experimentally and predicted theoretically early. Neutrons are similar to fermionic atoms. We found free neutrons could be cooled to ultracold neutrons with very low energy by other colder neutral atoms which are cooled by the laser. These neutrons form neutron pairs with spin zero, and then ultracold neutron-pairs form Bose-Einstein condensate. Our results demonstrate how these condensates can react with accelerated ion beams at different energy to synthesize very neutron-rich nuclides near, on or/and beyond the neutron drip line, to determine the neutron drip line and whether there are long-life nuclide or isomer islands beyond the neutron drip line experimentally. Otherwise, these experimental results will confirm our prediction that is in the whole interacting region or distance of nuclear force in all energy region from zero to infinite, Only repulsive nuclear force exists among identical nucleons and only among different nucleons exists attractive nuclear force.

  16. Neutronic Characterization of the Megapie Target

    E-Print Network [OSTI]

    Stefano Panebianco; Olivier Bringer; Pavel Bokov; Sebastien Chabod; Frederic Chartier; Emmeric Dupont; Diane Dore; Xavier Ledoux; Alain Letourneau; Ludovic Oriol; Aurelien Prevost; Danas Ridikas; Jean-Christian Toussaint

    2007-10-31T23:59:59.000Z

    The MEGAPIE project is one of the key experiments towards the feasibility of Accelerator Driven Systems. On-line operation and post-irradiation analysis will provide the scientific community with unique data on the behavior of a liquid spallation target under realistic irradiation conditions. A good neutronics performance of such a target is of primary importance towards an intense neutron source, where an extended liquid metal loop requires some dedicated verifications related to the delayed neutron activity of the irradiated PbBi. In this paper we report on the experimental characterization of the MEGAPIE neutronics in terms of the prompt neutron (PN) flux inside the target and the delayed neutron (DN) flux on the top of it. For the PN measurements, a complex detector, made of 8 microscopic fission chambers, has been built and installed in the central part of the target to measure the absolute neutron flux and its spatial distribution. Moreover, integral information on the neutron energy distribution as a function of the position along the beam axis could be extracted, providing integral constraints on the neutron production models implemented in transport codes such as MCNPX. For the DN measurement, we used a standard 3He counter and we acquired data during the start-up phase of the target irradiation in order to take sufficient statistics at variable beam power. Experimental results obtained on the PN flux characteristics and their comparison with MCNPX simulations are presented, together with a preliminary analysis of the DN decay time spectrum.

  17. Fusion Induced by Radioactive Ion Beams

    E-Print Network [OSTI]

    J. F. Liang; C. Signorini

    2005-04-26T23:59:59.000Z

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

  18. Development of an instrument for non-destructive identification of Unexploded Ordnance using tagged neutrons - a proof of concept study

    SciTech Connect (OSTI)

    Mitra, S.; Dioszegi, I.

    2011-10-23T23:59:59.000Z

    Range clearance operations at munitions testing grounds must discriminate Unexploded Ordnance (UXO) from clutter items and distinguish UXO filled with High Explosives (HE) from those with inert fillers. Non-destructive technologies are thus necessary for the cost-effective disposal of UXO during remediation of such sites. The only technique showing promise so far for the non-destructive elemental characterization of UXO fillers utilizes neutron interactions with the material to detect carbon (C), nitrogen (N) and oxygen (O) which have unique ratios in HE. However, several unresolved issues hinder the wide application of this potentially very suitable technique. The most important one is that neutrons interact with all surrounding matter in addition to the interrogated material, leading to a very high gamma-ray background in the detector. Systems requiring bulky shielding and having poor signal-to-noise ratios (SNRs) for measuring elements are unsuitable for field deployment. The inadequacies of conventional neutron interrogation methods are overcome by using the tagged-neutron approach, and the availability of compact sealed neutron generators exploiting this technique offers field deployment of non-intrusive measurement systems for detecting threat materials, like explosives and drugs. By accelerating deuterium ions into a tritium target, the subsequent fusion reaction generates nearly back-to-back emissions of neutrons and alpha particles of energy 14.1 and 3.5 MeV respectively. A position-sensitive detector recognizes the associated alpha particle, thus furnishing the direction of the neutron. The tagged neutrons interact with the nuclei of the interrogated object, producing element-specific prompt gamma-rays that the gamma detectors recognize. Measuring the delay between the detections of the alpha particle and the gamma-ray determines where the reaction occurred along the axis of the neutron beam (14.1 MeV neutrons travel at 5 cm/nanosecond, while gamma rays cover 30 cm/nanosecond). The main advantage of the technique is its ability to simultaneously provide 2D and 3D imaging of objects and their elemental composition. This work reports on the efficacy of using 14 MeV neutrons tagged by the associated particle neutron time-of-flight technique (APnTOF) to extract neutron induced characteristic gamma-rays from an object-of-interest with high SNR and without interference from nearby clutter.

  19. Thermal neutron detection system

    DOE Patents [OSTI]

    Peurrung, Anthony J. (Richland, WA); Stromswold, David C. (West Richland, WA)

    2000-01-01T23:59:59.000Z

    According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

  20. Spectrum tailoring of the neutron energy spectrum in the context of delayed neutron detection

    SciTech Connect (OSTI)

    Koehler, William E [Los Alamos National Laboratory; Tobin, Steve J [Los Alamos National Laboratory; Sandoval, Nathan P [Los Alamos National Laboratory; Fensin, Mike L [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    For the purpose of measuring plutonium mass in spent fuel, a delayed neutron instrument is of particular interest since, if properly designed, the delayed neutron signal from {sup 235}U is significantly stronger than the signature from {sup 239}Pu or {sup 241}Pu. A key factor in properly designing a delayed neutron instrument is to minimize the fission of {sup 238}U. This minimization is achieved by keeping the interrogating neutron spectrum below {approx} 1 MeV. In the context of spent fuel measurements it is desirable to use a 14 MeV (deuterium and tritium) neutron generator for economic reasons. Spectrum tailoring is the term used to describe the inclusion of material between the 14 MeV neutrons and the interrogated object that lower the neutron energy through nuclear reactions and moderation. This report quantifies the utility of different material combination for spectrum tailoring.

  1. Ion sources for sealed neutron tubes

    SciTech Connect (OSTI)

    Burns, E.J.T. [Sandia National Labs., Albuquerque, NM (United States). Neutron Tube Dept.; Bischoff, G.C. [Lockheed Martin Specialty Components, Largo, FL (United States)

    1996-11-01T23:59:59.000Z

    Fast and thermal neutron activation analysis with sealed neutron generators has been used to detect oil (oil logging), hazardous waste, fissile material, explosives, and contraband (drugs). Sealed neutron generators, used in the above applications, must be small and portable, have good electrical efficiency and long life. The ion sources used in the sealed neutron tubes require high gas utilization efficiencies or low pressure operation with high ionization efficiencies. In this paper, the authors compare a number of gas ion sources that can be used in sealed neutron tubes. The characteristics of the most popular ion source, the axial Penning discharge will be discussed as part of the zetatron neutron generator. Other sources to be discussed include the SAMIS source and RF ion source.

  2. Luminosity and beam-beam

    E-Print Network [OSTI]

    Papotti, G; Trad, G

    We report on observations on luminosity evolution and beam-beam interaction from the 2011 physics run. Extrapolations for 2012 are attempted and a list of desired studies and machine developments is included.

  3. - and -delayed neutron- decay of neutron-rich copper isotopes

    SciTech Connect (OSTI)

    Korgul, A. [University of Warsaw; Rykaczewski, Krzysztof Piotr [ORNL; Winger, J. A. [Oak Ridge Associated Universities (ORAU); Ilyushkin, S. [Mississippi State University (MSU); Gross, Carl J [ORNL; Batchelder, J. C. [Oak Ridge Associated Universities (ORAU); Bingham, C. R. [University of Tennessee, Knoxville (UTK); Borzov, Ivan N [ORNL; Goodin, C. [Vanderbilt University; Grzywacz, Robert Kazimierz [ORNL; Hamilton, Joseph H [ORNL; Krolas, W. [Joint Institute for Heavy Ion Research, Oak Ridge; Liddick, S. N. [Oak Ridge Associated Universities (ORAU); Mazzocchi, C. [University of Warsaw; Nelson, C. [Vanderbilt University; Nowacki, F. [Institut Pluridisciplinaire Hubert Curien, Strasbourg, France; Padgett, Stephen [University of Tennessee, Knoxville (UTK); Piechaczek, A. [Louisiana State University; Rajabali, M. M. [University of Tennessee, Knoxville (UTK); Shapira, Dan [ORNL; Sieja, K. [Technische Universitat Darmstadt, Germany; Zganjar, E. F. [Louisiana State University

    2012-01-01T23:59:59.000Z

    The {beta}-decay properties of neutron-rich Cu isotopes produced in proton-induced fission of {sup 238}U were studied at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. The data were collected using high-resolution online mass separation, reacceleration, and digital {beta}-{gamma} spectroscopy methods. An improved decay scheme of N = 49 {sup 78}Cu and the first observation of N = 50 {sup 79}Cu {beta}-delayed neutron decay followed by a gamma transition are reported. Spin and parity (5{sup -}) are deduced for {sup 78gs}Cu. The {beta}-delayed neutron branching ratios (P{sub {beta}n}) for the {sup 77}Cu and {sup 79}Cu precursors are analyzed with the help of nuclear structure models.

  4. Ion beam generating apparatus

    DOE Patents [OSTI]

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

    1987-01-01T23:59:59.000Z

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

  5. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, I.G.; Galvin, J.

    1987-12-22T23:59:59.000Z

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

  6. Neutron production enhancements for the Intense Pulsed Neutron Source.

    SciTech Connect (OSTI)

    Iverson, E. B.

    1999-01-04T23:59:59.000Z

    The Intense Pulsed Neutron Source (IPNS) was the first high energy spallation neutron source in the US dedicated to materials research. It has operated for sixteen years, and in that time has had a very prolific record concerning the development of new target and moderator systems for pulsed spallation sources. IPNS supports a very productive user program on its thirteen instruments, which are oversubscribed by more than two times, meanwhile having an excellent overall reliability of 95%. Although the proton beam power is relatively low at 7 kW, the target and moderator systems are very efficient. The typical beam power which gives an equivalent flux for long-wavelength neutrons is about 60 kW, due to the use of a uranium target and liquid and solid methane moderators, precluded at some sources due to a higher accelerator power. The development of new target and moderator systems is by no means stagnant at IPNS. They are presently considering numerous enhancements to the target and moderators that offer prospects for increasing the useful neutron production by substantial factors. Many of these enhancements could be combined, although their combined benefit has not yet been well established. Meanwhile, IPNS is embarking on a coherent program of study concerning these improvements and their possible combination and implementation. Moreover, any improvements accomplished at IPNS would immediately increase the performance of IPNS instruments.

  7. WNR Group Leader Steve Wender LANSCE Neutron Testing Facility

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

    an 800-MeV pulsed proton beam, with currents of approximately 5 A, that strikes a tungsten target. The impact produces a spectrum of neutrons whose energy distribution and...

  8. The neutron long counter NERO for studies of beta-delayed neutron emission in the r-process

    E-Print Network [OSTI]

    Pereira, J; Lorusso, G; Santi, P; Couture, A; Daly, J; Del Santo, M; Elliot, T; Goerres, J; Herlitzius, C; Kratz, K -L; Lamm, L O; Lee, H Y; Montes, F; Ouellette, M; Pellegrini, E; Reeder, P; Schatz, H; Schertz, F; Schnorrenberger, L; Smith, K; Stech, E; Strandberg, E; Ugalde, C; Wiescher, M; Woehr, A; 10.1016/j.nima.2010.02.262

    2010-01-01T23:59:59.000Z

    The neutron long counter NERO was built at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, for measuring beta-delayed neutron-emission probabilities. The detector was designed to work in conjunction with a beta-decay implantation station, so that beta decays and beta-delayed neutrons emitted from implanted nuclei can be measured simultaneously. The high efficiency of about 40%, for the range of energies of interest, along with the small background, are crucial for measuring beta-delayed neutron emission branchings for neutron-rich r-process nuclei produced as low intensity fragmentation beams in in-flight separator facilities.

  9. The neutron long counter NERO for studies of beta-delayed neutron emission in the r-process

    E-Print Network [OSTI]

    J. Pereira; P. Hosmer; G. Lorusso; P. Santi; A. Couture; J. Daly; M. Del Santo; T. Elliot; J. Goerres; C. Herlitzius; K. -L. Kratz; L. O. Lamm; H. Y. Lee; F. Montes; M. Ouellette; E. Pellegrini; P. Reeder; H. Schatz; F. Schertz; L. Schnorrenberger; K. Smith; E. Stech; E. Strandberg; C. Ugalde; M. Wiescher; A. Woehr

    2010-07-28T23:59:59.000Z

    The neutron long counter NERO was built at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, for measuring beta-delayed neutron-emission probabilities. The detector was designed to work in conjunction with a beta-decay implantation station, so that beta decays and beta-delayed neutrons emitted from implanted nuclei can be measured simultaneously. The high efficiency of about 40%, for the range of energies of interest, along with the small background, are crucial for measuring beta-delayed neutron emission branchings for neutron-rich r-process nuclei produced as low intensity fragmentation beams in in-flight separator facilities.

  10. Recent advances in neutron capture therapy (NCT)

    SciTech Connect (OSTI)

    Fairchild, R.G.

    1985-01-01T23:59:59.000Z

    The application of the /sup 10/B(n,..cap alpha..)/sup 7/Li reaction to cancer radiotherapy (Neutron Capture therapy, or NCT) has intrigued investigators since the discovery of the neutron. This paper briefly summarizes data describing recently developed boronated compounds with evident tumor specificity and extended biological half-lives. The implication of these compounds to NCT is evaluated in terms of Therapeutic Gain (TG). The optimization of NCT using band-pass filtered beams is described, again in terms of TG, and irradiation times with these less intense beams are estimated. 24 refs., 3 figs., 3 tabs.

  11. Epithermal Neutron Source for Neutron Resonance Spectroscopy (NRS) using High Intensity, Short Pulse Lasers

    SciTech Connect (OSTI)

    Higginson, D P; McNaney, J M; Swift, D C; Bartal, T; Hey, D S; Pape, S L; Mackinnon, A; Mariscal, D; Nakamura, H; Nakanii, N; Beg, F N

    2010-04-22T23:59:59.000Z

    A neutron source for neutron resonance spectroscopy (NRS) has been developed using high intensity, short pulse lasers. This measurement technique will allow for robust measurements of interior ion temperature of laser-shocked materials and provide insight into equation of state (EOS) measurements. The neutron generation technique uses protons accelerated by lasers off of Cu foils to create neutrons in LiF, through (p,n) reactions with {sup 7}Li and {sup 19}F. The distribution of the incident proton beam has been diagnosed using radiochromic film (RCF). This distribution is used as the input for a (p,n) neturon prediction code which is compared to experimentally measured neutron yields. From this calculation, a total fluence of 1.8 x 10{sup 9} neutrons is infered, which is shown to be a reasonable amount for NRS temperature measurement.

  12. Superconducting magnetic Wollaston prism for neutron spin encoding

    SciTech Connect (OSTI)

    Li, F., E-mail: fankli@indiana.edu; Parnell, S. R.; Wang, T.; Baxter, D. V. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States)] [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Hamilton, W. A. [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)] [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States); Maranville, B. B. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)] [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Semerad, R. [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany)] [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany); Cremer, J. T. [Adelphi Technology Inc., Redwood City, California 94063 (United States)] [Adelphi Technology Inc., Redwood City, California 94063 (United States); Pynn, R. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States) [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)

    2014-05-15T23:59:59.000Z

    A magnetic Wollaston prism can spatially split a polarized neutron beam into two beams with different neutron spin states, in a manner analogous to an optical Wollaston prism. Such a Wollaston prism can be used to encode the trajectory of neutrons into the Larmor phase associated with their spin degree of freedom. This encoding can be used for neutron phase-contrast radiography and in spin echo scattering angle measurement (SESAME). In this paper, we show that magnetic Wollaston prisms with highly uniform magnetic fields and low Larmor phase aberration can be constructed to preserve neutron polarization using high temperature superconducting (HTS) materials. The Meissner effect of HTS films is used to confine magnetic fields produced electromagnetically by current-carrying HTS tape wound on suitably shaped soft iron pole pieces. The device is cooled to ?30 K by a closed cycle refrigerator, eliminating the need to replenish liquid cryogens and greatly simplifying operation and maintenance. A HTS film ensures that the magnetic field transition within the prism is sharp, well-defined, and planar due to the Meissner effect. The spin transport efficiency across the device was measured to be ?98.5% independent of neutron wavelength and energizing current. The position-dependent Larmor phase of neutron spins was measured at the NIST Center for Neutron Research facility and found to agree well with detailed simulations. The phase varies linearly with horizontal position, as required, and the neutron beam shows little depolarization. Consequently, the device has advantages over existing devices with similar functionality and provides the capability for a large neutron beam (20 mm × 30 mm) and an increase in length scales accessible to SESAME to beyond 10 ?m. With further improvements of the external coupling guide field in the prototype device, a larger neutron beam could be employed.

  13. Neutron Repulsion

    E-Print Network [OSTI]

    Oliver K. Manuel

    2011-02-08T23:59:59.000Z

    Earth is connected gravitationally, magnetically and electrically to its heat source - a neutron star that is obscured from view by waste products in the photosphere. Neutron repulsion is like the hot filament in an incandescent light bulb. Excited neutrons are emitted from the solar core and decay into hydrogen that glows in the photosphere like a frosted light bulb. Neutron repulsion was recognized in nuclear rest mass data in 2000 as the overlooked source of energy, the keystone of an arch that locked together these puzzling space-age observations: 1.) Excess 136Xe accompanied primordial helium in the stellar debris that formed the solar system (Fig. 1); 2.) The Sun formed on the supernova core (Fig. 2); 3.) Waste products from the core pass through an iron-rich mantle, selectively carrying lighter elements and lighter isotopes of each element into the photosphere (Figs. 3-4); and 4.) Neutron repulsion powers the Sun and sustains life (Figs. 5-7). Together these findings offer a framework for understanding how: a.) The Sun generates and releases neutrinos, energy and solar-wind hydrogen and helium; b.) An inhabitable planet formed and life evolved around an ordinary-looking star; c.) Continuous climate change - induced by cyclic changes in gravitational interactions of the Sun's energetic core with planets - has favored survival by adaptation.

  14. Neutron Repulsion

    E-Print Network [OSTI]

    Manuel, Oliver K

    2011-01-01T23:59:59.000Z

    Earth is connected gravitationally, magnetically and electrically to its heat source - a neutron star that is obscured from view by waste products in the photosphere. Neutron repulsion is like the hot filament in an incandescent light bulb. Excited neutrons are emitted from the solar core and decay into hydrogen that glows in the photosphere like a frosted light bulb. Neutron repulsion was recognized in nuclear rest mass data in 2000 as the overlooked source of energy, the keystone of an arch that locked together these puzzling space-age observations: 1.) Excess 136Xe accompanied primordial helium in the stellar debris that formed the solar system (Fig. 1); 2.) The Sun formed on the supernova core (Fig. 2); 3.) Waste products from the core pass through an iron-rich mantle, selectively carrying lighter elements and lighter isotopes of each element into the photosphere (Figs. 3-4); and 4.) Neutron repulsion powers the Sun and sustains life (Figs. 5-7). Together these findings offer a framework for understanding...

  15. Optimized performance for neutron interrogation to detect SNM

    SciTech Connect (OSTI)

    Slaughter, D R; Asztalos, S J; Biltoft, P J; Church, J A; Descalle, M; Hall, J M; Luu, T C; Manatt, D R; Mauger, G J; Norman, E B; Petersen, D C; Pruet, J A; Prussin, S G

    2007-02-14T23:59:59.000Z

    A program of simulations and validating experiments was utilized to evaluate a concept for neutron interrogation of commercial cargo containers that would reliably detect special nuclear material (SNM). The goals were to develop an interrogation system capable of detecting a 5 kg solid sphere of high-enriched uranium (HEU) even when deeply embedded in commercial cargo. Performance goals included a minimum detection probability, P{sub d} {ge} 95%, a maximum occurrence of false positive indications, P{sub fA} {le} 0.001, and maximum scan duration of t {le} 1 min. The conditions necessary to meet these goals were demonstrated in experimental measurements even when the SNM is deeply buried in any commercial cargo, and are projected to be met successfully in the most challenging cases of steel or hydrocarbons at areal density {rho}L {le} 150 g/cm{sup 2}. Optimal performance was obtained with a collimated ({Delta}{Theta} = {+-} 15{sup o}) neutron beam at energy E{sub n} = 7 MeV produced by the D(d,n) reaction with the deuteron energy E{sub d} = 4 MeV. Two fission product signatures are utilized to uniquely identify SNM, including delayed neutrons detected in a large array of polyethylene moderated 3He proportional counters and high energy {beta}-delayed fission product {gamma}-radiation detected in a large array of 61 x 61 x 25 cm{sup 3} plastic scintillators. The latter detectors are nearly blind to normal terrestrial background radiation by setting an energy threshold on the detection at E{sub min} {ge} 3 MeV. Detection goals were attained with a low beam current (I{sub d} = 15-65 {micro}A) source up to {rho}L = 75 g/cm{sup 2} utilizing long irradiations, T = 30 sec, and long counting times, t = 30-100 sec. Projecting to a higher beam current, I{sub d} {ge} 600 {micro}A and larger detector array the detection and false alarm goals would be attained even with intervening cargo overburden as large as {rho}L {le} 150 g/cm{sup 2}. The latter cargo thickness corresponds to 8 ft of hydrogenous or metallic cargo at the highest density allowed by the weight limit of the container. Simulations support the efficacy of this technique in the most challenging cases and experimental measurements are shown validating these predictions. Signal and background levels have been assessed and utilized to predict error rates due to false positive and false negative results. The laboratory system demonstrates the ability to detect HEU in amounts as small as m {ge} 250 g buried in the middle of a maximum density cargo and to do so with error rates that meet the goals given above. Higher beam current allows reliable SNM detection in shorter irradiation and/or counting times and with more challenging cargo threat scenarios.

  16. Enhanced reaction rates in NDP analysis with neutron scattering

    SciTech Connect (OSTI)

    Downing, R. Gregory, E-mail: gregory.downing@nist.gov [National Institute of Standards and Technology, Chemical Sciences Division, Gaithersburg, Maryland 20899 (United States)

    2014-04-15T23:59:59.000Z

    Neutron depth profiling (NDP) makes accessible quantitative information on a few isotopic concentration profiles ranging from the surface into the sample a few micrometers. Because the candidate analytes for NDP are few, there is little interference encountered. Furthermore, neutrons have no charge so mixed chemical states in the sample are of no direct concern. There are a few nuclides that exhibit large probabilities for neutron scattering. The effect of neutron scattering on NDP measurements has not previously been evaluated as a basis for either enhancing the reaction rates or as a source of measurement error. Hydrogen is a common element exhibiting large neutron scattering probability found in or around sample volumes being analyzed by NDP. A systematic study was conducted to determine the degree of signal change when neutron scattering occurs during analysis. The relative signal perturbation was evaluated for materials of varied neutron scattering probability, concentration, total mass, and geometry. Signal enhancements up to 50% are observed when the hydrogen density is high and in close proximity to the region of analysis with neutron beams of sub thermal energies. Greater signal enhancements for the same neutron number density are reported for thermal neutron beams. Even adhesive tape used to position the sample produces a measureable signal enhancement. Because of the shallow volume, negligible distortion of the NDP measured profile shape is encountered from neutron scattering.

  17. RIS-M-2356 STANDARDIZATION ACTIVITIES OF THE EURATOM NEUTRON

    E-Print Network [OSTI]

    for assessing the results of neutron radio- graphic testing). Methods and equipment for accurately measuring HON Neutron radiography is a well-established technique within non-destructive testing control. One is illustrated in a special atlas. Beam purity and sensitivity indicators are tested together with a special

  18. Characterizing and Controlling Beam Losses at the LANSCE Facility

    SciTech Connect (OSTI)

    Rybarcyk, Lawrence J. [Los Alamos National Laboratory

    2012-09-12T23:59:59.000Z

    The Los Alamos Neutron Science Center (LANSCE) currently provides 100-MeV H{sup +} and 800-MeV H{sup -} beams to several user facilities that have distinct beam requirements, e.g. intensity, micropulse pattern, duty factor, etc. Minimizing beam loss is critical to achieving good performance and reliable operation, but can be challenging in the context of simultaneous multi-beam delivery. This presentation will discuss various aspects related to the observation, characterization and minimization of beam loss associated with normal production beam operations in the linac.

  19. High temperature furnaces for small and large angle neutron scattering of disordered materials

    E-Print Network [OSTI]

    Boyer, Edmond

    725 High temperature furnaces for small and large angle neutron scattering of disordered materials and small angle neutron scattering (SANS) experiments respectively. They are vacuum furnaces with a thin maintained in a tantalum box. In a neutron beam, the furnaces produce a very low scattering level (without

  20. Neutron Generators for Spent Fuel Assay

    SciTech Connect (OSTI)

    Ludewigt, Bernhard A

    2010-12-30T23:59:59.000Z

    The Next Generation Safeguards Initiative (NGSI) of the U.S. DOE has initiated a multi-lab/university collaboration to quantify the plutonium (Pu) mass in, and detect the diversion of pins from, spent nuclear fuel (SNF) assemblies with non-destructive assay (NDA). The 14 NDA techniques being studied include several that require an external neutron source: Delayed Neutrons (DN), Differential Die-Away (DDA), Delayed Gammas (DG), and Lead Slowing-Down Spectroscopy (LSDS). This report provides a survey of currently available neutron sources and their underlying technology that may be suitable for NDA of SNF assemblies. The neutron sources considered here fall into two broad categories. The term 'neutron generator' is commonly used for sealed devices that operate at relatively low acceleration voltages of less than 150 kV. Systems that employ an acceleration structure to produce ion beam energies from hundreds of keV to several MeV, and that are pumped down to vacuum during operation, rather than being sealed units, are usually referred to as 'accelerator-driven neutron sources.' Currently available neutron sources and future options are evaluated within the parameter space of the neutron generator/source requirements as currently understood and summarized in section 2. Applicable neutron source technologies are described in section 3. Commercially available neutron generators and other source options that could be made available in the near future with some further development and customization are discussed in sections 4 and 5, respectively. The pros and cons of the various options and possible ways forward are discussed in section 6. Selection of the best approach must take a number of parameters into account including cost, size, lifetime, and power consumption, as well as neutron flux, neutron energy spectrum, and pulse structure that satisfy the requirements of the NDA instrument to be built.

  1. Federal Utility Partnership Working Group Utility Partners

    Broader source: Energy.gov [DOE]

    Federal Utility Partnership Working Group (FUPWG) utility partners are eager to work closely with Federal agencies to help achieve energy management goals.

  2. The Neutron Imaging Diagnostic at NIF

    SciTech Connect (OSTI)

    Merrill, F E; Buckles, R; Clark, D; Danly, C R; Drury, O B; Dzenitis, J M; Fatherly, V E; Fittinghoff, D N; Gallegos, R; Grim, G P; Guler, N; Loomis, E N; Lutz, S; Malone, R M; Martinson, D D; Mares, D; Morley, D J; Morgan, G L; Oertel, J A; Tregillis, I L; Volegov, P L; Weiss, P B; Wilde, C H

    2012-10-01T23:59:59.000Z

    A neutron imaging diagnostic has recently been commissioned at the National Ignition Facility (NIF). This new system is an important diagnostic tool for inertial fusion studies at the NIF for measuring the size and shape of the burning DT plasma during the ignition stage of ICF implosions. The imaging technique utilizes a pinhole neutron aperture, placed between the neutron source and a neutron detector. The detection system measures the two dimensional distribution of neutrons passing through the pinhole. This diagnostic has been designed to collect two images at two times. The long flight path for this diagnostic, 28 m, results in a chromatic separation of the neutrons, allowing the independently timed images to measure the source distribution for two neutron energies. Typically the first image measures the distribution of the 14 MeV neutrons and the second image of the 6-12 MeV neutrons. The combination of these two images has provided data on the size and shape of the burning plasma within the compressed capsule, as well as a measure of the quantity and spatial distribution of the cold fuel surrounding this core.

  3. Extracting source parameters from beam monitors on a chopper spectrometer

    SciTech Connect (OSTI)

    Abernathy, Douglas L [ORNL; Niedziela, Jennifer L [ORNL; Stone, Matthew B [ORNL

    2015-01-01T23:59:59.000Z

    The intensity distributions of beam monitors in direct-geometry time-of-flight neutron spectrometers provide important information about the instrument resolution. For short-pulse spallation neutron sources in particular, the asymmetry of the source pulse may be extracted and compared to Monte Carlo source simulations. An explicit formula using a Gaussian-convolved Ikeda-Carpenter distribution is given and compared to data from the ARCS instrument at the Spallation Neutron Source.

  4. Methods for absorbing neutrons

    DOE Patents [OSTI]

    Guillen, Donna P. (Idaho Falls, ID); Longhurst, Glen R. (Idaho Falls, ID); Porter, Douglas L. (Idaho Falls, ID); Parry, James R. (Idaho Falls, ID)

    2012-07-24T23:59:59.000Z

    A conduction cooled neutron absorber may include a metal matrix composite that comprises a metal having a thermal neutron cross-section of at least about 50 barns and a metal having a thermal conductivity of at least about 1 W/cmK. Apparatus for providing a neutron flux having a high fast-to-thermal neutron ratio may include a source of neutrons that produces fast neutrons and thermal neutrons. A neutron absorber positioned adjacent the neutron source absorbs at least some of the thermal neutrons so that a region adjacent the neutron absorber has a fast-to-thermal neutron ratio of at least about 15. A coolant in thermal contact with the neutron absorber removes heat from the neutron absorber.

  5. Conceptual Design for Replacement of the DTL and CCL with Superconducting RF Cavities in the Spallation Neutron Source Linac

    SciTech Connect (OSTI)

    Champion, Mark S [ORNL] [ORNL; Doleans, Marc [ORNL] [ORNL; Kim, Sang-Ho [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    The Spallation Neutron Source Linac utilizes normal conducting RF cavities in the low energy section from 2.5 MeV to 186 MeV. Six Drift Tube Linac (DTL) structures accelerate the beam to 87 MeV, and four Coupled Cavity Linac (CCL) structures provide further acceleration to 186 MeV. The remainder of the Linac is comprised of 81 superconducting cavities packaged in 23 cryomodules to provide final beam energy of approximately 1 GeV. The superconducting Linac has proven to be substantially more reliable than the normal conducting Linac despite the greater number of stations and the complexity associated with the cryogenic plant and distribution. A conceptual design has been initiated on a replacement of the DTL and CCL with superconducting RF cavities. The motivation, constraints, and conceptual design are presented.

  6. Delayed and In-beam Spectroscopy on Francium and Astatine Nuclei at the Proton Drip Line

    SciTech Connect (OSTI)

    Uusitalo, J.; Jakobsson, U. [Department of Physics, University of Jyvaeskylae (Finland); Collaboration: RITU-Gamma Gollaboration

    2011-11-30T23:59:59.000Z

    Delayed and in-beam spectroscopy on francium and astatine nuclei at and beyond the proton drip line has been performed. In neutron deficient astatine nuclei a shift to deformed shapes as a function of decreasing neutron has been obtained. In neutron deficient francium isotope the same shift is evident.

  7. Neutron reflecting supermirror structure

    DOE Patents [OSTI]

    Wood, James L. (Drayton Plains, MI)

    1992-01-01T23:59:59.000Z

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources.

  8. Neutron reflecting supermirror structure

    DOE Patents [OSTI]

    Wood, J.L.

    1992-12-01T23:59:59.000Z

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. 2 figs.

  9. Design and demonstration of a quasi-monoenergetic neutron source

    E-Print Network [OSTI]

    T. H. Joshi; S. Sangiorgio; V. Mozin; E. B. Norman; P. Sorensen; M. Foxe; G. Bench; A. Bernstein

    2014-05-13T23:59:59.000Z

    The design of a neutron source capable of producing 24 and 70 keV neutron beams with narrow energy spread is presented. The source exploits near-threshold kinematics of the $^{7}$Li(p,n)$^{7}$Be reaction while taking advantage of the interference `notches' found in the scattering cross-sections of iron. The design was implemented and characterized at the Center for Accelerator Mass Spectrometry at Lawrence Livermore National Laboratory. Alternative filters such as vanadium and manganese are also explored and the possibility of studying the response of different materials to low-energy nuclear recoils using the resultant neutron beams is discussed.

  10. Design and Demonstration of a Quasi-monoenergetic Neutron Source

    SciTech Connect (OSTI)

    Joshi, T.; Sangiorgio, Samuele; Mozin, Vladimir V.; Norman, E. B.; Sorensen, Peter F.; Foxe, Michael P.; Bench, G.; Bernstein, A.

    2014-03-05T23:59:59.000Z

    The design of a neutron source capable of producing 24 and 70 keV neutron beams with narrow energy spread is presented. The source exploits near-threshold kinematics of the 7Li(p,n)7Be reaction while taking advantage of the interference `notches' found in the scattering cross-sections of iron. The design was implemented and characterized at the Center for Accelerator Mass Spectrometry at Lawrence Livermore National Laboratory. Alternative lters such as vanadium and manganese are also explored and the possibility of studying the response of di*erent materials to low-energy nuclear recoils using the resultant neutron beams is discussed.

  11. Pitfalls of tungsten multileaf collimator in proton beam therapy

    SciTech Connect (OSTI)

    Moskvin, Vadim; Cheng, Chee-Wai; Das, Indra J. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202 (United States) and Indiana University Health Proton Therapy Center (Formerly Midwest Proton Radiotherapy Institute), Bloomington, Indiana 47408 (United States)

    2011-12-15T23:59:59.000Z

    Purpose: Particle beam therapy is associated with significant startup and operational cost. Multileaf collimator (MLC) provides an attractive option to improve the efficiency and reduce the treatment cost. A direct transfer of the MLC technology from external beam radiation therapy is intuitively straightforward to proton therapy. However, activation, neutron production, and the associated secondary cancer risk in proton beam should be an important consideration which is evaluated. Methods: Monte Carlo simulation with FLUKA particle transport code was applied in this study for a number of treatment models. The authors have performed a detailed study of the neutron generation, ambient dose equivalent [H*(10)], and activation of a typical tungsten MLC and compared with those obtained from a brass aperture used in a typical proton therapy system. Brass aperture and tungsten MLC were modeled by absorber blocks in this study, representing worst-case scenario of a fully closed collimator. Results: With a tungsten MLC, the secondary neutron dose to the patient is at least 1.5 times higher than that from a brass aperture. The H*(10) from a tungsten MLC at 10 cm downstream is about 22.3 mSv/Gy delivered to water phantom by noncollimated 200 MeV beam of 20 cm diameter compared to 14 mSv/Gy for the brass aperture. For a 30-fraction treatment course, the activity per unit volume in brass aperture reaches 5.3 x 10{sup 4} Bq cm{sup -3} at the end of the last treatment. The activity in brass decreases by a factor of 380 after 24 h, additional 6.2 times after 40 days of cooling, and is reduced to background level after 1 yr. Initial activity in tungsten after 30 days of treating 30 patients per day is about 3.4 times higher than in brass that decreases only by a factor of 2 after 40 days and accumulates to 1.2 x 10{sup 6} Bq cm{sup -3} after a full year of operation. The daily utilization of the MLC leads to buildup of activity with time. The overall activity continues to increase due to {sup 179}Ta with a half-life of 1.82 yr and thus require prolonged storage for activity cooling. The H*(10) near the patient side of the tungsten block is about 100 {mu}Sv/h and is 27 times higher at the upstream side of the block. This would lead to an accumulated dose for therapists in a year that may exceed occupational maximum permissible dose (50 mSv/yr). The value of H*(10) at the upstream surface of the tungsten block is about 220 times higher than that of the brass. Conclusions: MLC is an efficient way for beam shaping and overall cost reduction device in proton therapy. However, based on this study, tungsten seems to be not an optimal material for MLC in proton beam therapy. Usage of tungsten MLC in clinic may create unnecessary risks associated with the secondary neutrons and induced radioactivity for patients and staff depending on the patient load. A careful selection of material for manufacturing of an optimal MLC for proton therapy is thus desired.

  12. ORNL Neutron Sciences Annual Report for 2007

    SciTech Connect (OSTI)

    Anderson, Ian S [ORNL; Horak, Charlie M [ORNL; Counce, Deborah Melinda [ORNL; Ekkebus, Allen E [ORNL

    2008-07-01T23:59:59.000Z

    This is the first annual report of the Oak Ridge National Laboratory Neutron Sciences Directorate for calendar year 2007. It describes the neutron science facilities, current developments, and future plans; highlights of the year's activities and scientific research; and information on the user program. It also contains information about education and outreach activities and about the organization and staff. The Neutron Sciences Directorate is responsible for operation of the High Flux Isotope Reactor and the Spallation Neutron Source. The main highlights of 2007 were highly successful operation and instrument commissioning at both facilities. At HFIR, the year began with the reactor in shutdown mode and work on the new cold source progressing as planned. The restart on May 16, with the cold source operating, was a significant achievement. Furthermore, measurements of the cold source showed that the performance exceeded expectations, making it one of the world's most brilliant sources of cold neutrons. HFIR finished the year having completed five run cycles and 5,880 MWd of operation. At SNS, the year began with 20 kW of beam power on target; and thanks to a highly motivated staff, we reached a record-breaking power level of 183 kW by the end of the year. Integrated beam power delivered to the target was 160 MWh. Although this is a substantial accomplishment, the next year will bring the challenge of increasing the integrated beam power delivered to 887 MWh as we chart our path toward 5,350 MWh by 2011.

  13. Self-regulating neutron coincidence counter

    DOE Patents [OSTI]

    Baron, N.

    1980-06-16T23:59:59.000Z

    A device for accurately measuring the mass of /sup 240/Pu and /sup 239/Pu in a sample having arbitrary moderation and mixed with various contaminants. The device utilizes a thermal neutron well counter which has two concentric rings of neutron detectors separated by a moderating material surrounding the well. Neutron spectroscopic information derived by the two rings of detectors is used to measure the quantity of /sup 239/Pu and /sup 240/Pu in device which corrects for background radiation, deadtime losses of the detector and electronics and various other constants of the system.

  14. Utility Partnerships Webinar Series: Gas Utility Energy Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Utility Partnerships Webinar Series: Gas Utility Energy Efficiency Programs Utility Partnerships Webinar Series: Gas Utility Energy Efficiency Programs gasutilityeewebinarnov2...

  15. Yield of delayed neutrons in the thermal-neutron-induced reaction {sup 245}Cm(n, f)

    SciTech Connect (OSTI)

    Andrianov, V. R. [Joint Institute for Nuclear Research (Russian Federation); Vyachin, V. N. [All-Russia Scientific Research Institute of Experimental Physics (VNIIEF) (Russian Federation); Gundorin, N. A. [Joint Institute for Nuclear Research (Russian Federation); Druzhinin, A. A. [All-Russia Scientific Research Institute of Experimental Physics (VNIIEF) (Russian Federation); Zhdanova, K. V.; Lihachev, A. N.; Pikelner, L. B.; Rebrova, N. V.; Salamatin, I. M.; Furman, V. I. [Joint Institute for Nuclear Research (Russian Federation)

    2008-10-15T23:59:59.000Z

    The yield of delayed neutrons, v{sub d}, from thermal-neutron-induced fission of {sup 245}Cm is measured. Experiments aimed at studying the properties of delayed neutrons from the fission of some reactor isotopes and initiated in 1997 were continued at the upgraded Isomer-M facility by a method according to which a periodic irradiation of a sample with a pulsed neutron beam from the IBR-2 reactor was accompanied by recording emitted neutrons in the intervals between the pulses. The accuracy of the resulting total delayed-neutron yield v{sub d} = (0.64 {+-} 0.02)% is two times higher than that in previous measurements. This work was performed at the Frank Laboratory of Neutron Physics at the Joint Institute for Nuclear Research (JINR, Dubna).

  16. Nuclear-spectroscopy problems studied with neutrons

    SciTech Connect (OSTI)

    Raman, S.

    1982-01-01T23:59:59.000Z

    Nuclear spectroscopy with neutrons continues to have a major impact on the progress of nuclear science. Neutrons, being uncharged, are particularly useful for the study of low energy reactions. Recent advances in time-of-flight spectroscopy, as well as in the gamma ray spectroscopy following neutron capture, have permitted precision studies of unbound and bound nuclear levels and related phenomena. By going to new energy domains, by using polarized beams and targets, through the invention of new kinds of detectors, and through the general improvement in beam quantity and quality, new features of nuclear structure and reactions have been obtained that are not ony interesting per se but are also grist for old and new theory mills. The above technical advances have opened up new opportunities for further discoveries.

  17. Imprinted spiral structures as neutron polarizers.

    SciTech Connect (OSTI)

    Lohstroh, W.

    1998-10-07T23:59:59.000Z

    Neutron diffraction from magnetic spiral structures is governed by strong selection rules for the polarization of the outgoing beam. When the sample is entirely of one chirality--for instance a right handed spiral--the neutrons diffracted by some Bragg reflections are fully polarized. While the scattering theory has been formulated long ago, attempts to controllably modify the population of left handed and right handed spiral domains in natural magnetic structures (which for instance occur in some rare earth metals) have been largely unsuccessful. In contrast, we have been able to imprint helical magnetic structures in La/Fe multilayers (each layer approximately 30 {angstrom} thick) simply by rotating the growing sample in a weak external field (30e). A first estimate is given of the efficiency of these multilayers as polarizers of neutron beams.

  18. NET PRED UTILITY

    Energy Science and Technology Software Center (OSTI)

    002602IBMPC00 Normalized Elution Time Prediction Utility  http://omics.pnl.gov/software/NETPredictionUtility.php 

  19. High-Yield D-T Neutron Generator

    SciTech Connect (OSTI)

    Ludewigt, B.A.; Wells, R.P.; Reijonen, J.

    2006-11-15T23:59:59.000Z

    A high-yield D-T neutron generator has been developed for neutron interrogation in homeland security applications such as cargo screening. The generator has been designed as a sealed tube with a performance goal of producing 5 {center_dot} 10{sup 11} n/s over a long lifetime. The key generator components developed are a radio-frequency (RF) driven ion source and a beam-loaded neutron production target that can handle a beam power of 10 kW. The ion source can provide a 100 mA D{sup +}/T{sup +} beam current with a high fraction of atomic species and can be pulsed up to frequencies of several kHz for pulsed neutron generator operation. Testing in D-D operation has been started.

  20. Radiobiology of normal rat lung in Boron Neutron Capture Therapy

    E-Print Network [OSTI]

    Kiger, Jingli Liu

    2006-01-01T23:59:59.000Z

    Boron Neutron Capture Therapy (BNCT) is a binary cancer radiation therapy that utilizes biochemical tumor cell targeting and provides a mixed field of high and low Linear Energy Transfer (LET) radiation with differing ...

  1. Ultra-short ion and neutron pulse production

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Barletta, William A.; Kwan, Joe W.

    2006-01-10T23:59:59.000Z

    An ion source has an extraction system configured to produce ultra-short ion pulses, i.e. pulses with pulse width of about 1 .mu.s or less, and a neutron source based on the ion source produces correspondingly ultra-short neutron pulses. To form a neutron source, a neutron generating target is positioned to receive an accelerated extracted ion beam from the ion source. To produce the ultra-short ion or neutron pulses, the apertures in the extraction system of the ion source are suitably sized to prevent ion leakage, the electrodes are suitably spaced, and the extraction voltage is controlled. The ion beam current leaving the source is regulated by applying ultra-short voltage pulses of a suitable voltage on the extraction electrode.

  2. Differential cross section for neutron-proton bremsstrahlung

    E-Print Network [OSTI]

    Y. Safkan; T. Akdogan; W. A. Franklin; J. L. Matthews; W. M. Schmitt; V. V. Zelevinsky; P. A. M. Gram; T. N. Taddeucci; S. A. Wender; S. F. Pate

    2007-03-21T23:59:59.000Z

    The neutron-proton bremsstrahlung process $(np \\to np\\gamma)$ is known to be sensitive to meson exchange currents in the nucleon-nucleon interaction. The triply differential cross section for this reaction has been measured for the first time at the Los Alamos Neutron Science Center, using an intense, pulsed beam of up to 700 MeV neutrons to bombard a liquid hydrogen target. Scattered neutrons were observed at six angles between 12$^\\circ$ and 32$^\\circ$, and the recoil protons were observed in coincidence at 12$^\\circ$, 20$^\\circ$, and 28$^\\circ$ on the opposite side of the beam. Measurement of the neutron and proton energies at known angles allows full kinematic reconstruction of each event. The data are compared with predictions of two theoretical calculations, based on relativistic soft-photon and non-relativistic potential models.

  3. Qualification tests of materials for spallation neutron sources

    SciTech Connect (OSTI)

    Sommer, W.F.

    1996-12-31T23:59:59.000Z

    Several existing and planned facilities, worldwide, use protons at 650-2000 MeV to produce neutrons by spallation reactions. In the advanced spallation neutron sources, materials in the target and blanket structures will be exposed to high-energy proton fluences at 10{sup 25}-10{sup 26}/m{sup 2} per year. Information obtained in fusion reactor studies are being applied to the design of spallation neutron sources. The APT project is sponsoring a materials qualification program including irradiations in the proton beam and neutron field at the Los Alamos Spallation Radiation Damage Facility.

  4. Neutron total cross section measurements of gold and tantalum at the nELBE photoneutron source

    E-Print Network [OSTI]

    Roland Hannaske; Zoltan Elekes; Roland Beyer; Arnd Junghans; Daniel Bemmerer; Evert Birgersson; Anna Ferrari; Eckart Grosse; Mathias Kempe; Toni Kögler; Michele Marta; Ralph Massarczyk; Andrija Matic; Georg Schramm; Ronald Schwengner; Andreas Wagner

    2013-11-05T23:59:59.000Z

    Neutron total cross sections of $^{197}$Au and $^\\text{nat}$Ta have been measured at the nELBE photoneutron source in the energy range from 0.1 - 10 MeV with a statistical uncertainty of up to 2 % and a total systematic uncertainty of 1 %. This facility is optimized for the fast neutron energy range and combines an excellent time structure of the neutron pulses (electron bunch width 5 ps) with a short flight path of 7 m. Because of the low instantaneous neutron flux transmission measurements of neutron total cross sections are possible, that exhibit very different beam and background conditions than found at other neutron sources.

  5. Studying of hypernuclei with nuclotron beams

    SciTech Connect (OSTI)

    Averyanov, A. V.; Avramenko, S. A.; Aksinenko, V. D.; Anikina, M. Kh.; Bazylev, S. N.; Balandin, V. P.; Batusov, Yu. A.; Belikov, Yu. A.; Borzunov, Yu. T.; Borodina, O. V.; Golokhvastov, A. I.; Golovanov, L. B. [Joint Institute for Nuclear Research (Russian Federation); Granja, C. [Czech Technical University, Institute of Experimental and Applied Physics (Czech Republic); Ivanov, A. B.; Ivanov, Yu. L.; Isupov, A. Yu. [Joint Institute for Nuclear Research (Russian Federation); Kohout, Z. [Czech Technical University (Czech Republic); Korotkova, A. M.; Litvinenko, A. G.; Lukstins, J., E-mail: juris@sunhe.jinr.r [Joint Institute for Nuclear Research (Russian Federation)

    2008-12-15T23:59:59.000Z

    A spectrometer is created to study relativistic hypernuclei produced with beams of accelerated nuclei from the Nuclotron facility (Dubna, JINR). Test runs have been carried out and the conclusion is drawn that the properties of the facility meet the requirements of the task of searching for unknown and studying poorly known neutron-rich hypernuclei.

  6. Cryogenic hydrogen circulation system of neutron source

    SciTech Connect (OSTI)

    Qiu, Y. N. [Institute of Physics and Chemistry, Chinese Academy of Sciences, BJ100190 China and University of Chinese Academy of Sciences, Chinese Academy of Sciences, BJ100049 (China); Hu, Z. J.; Wu, J. H.; Li, Q.; Zhang, Y. [Institute of Physics and Chemistry, Chinese Academy of Sciences, BJ100190 (China); Zhang, P. [School of Energy and Power Engineering, HuaZhong University of Science and Technology, WH430074 (China); Wang, G. P. [Institute of High Energy Physics, Chinese Academy of Sciences, BJ100049 (China)

    2014-01-29T23:59:59.000Z

    Cold neutron sources of reactors and spallation neutron sources are classic high flux neutron sources in operation all over the world. Cryogenic fluids such as supercritical or supercooled hydrogen are commonly selected as a moderator to absorb the nuclear heating from proton beams. By comparing supercritical hydrogen circulation systems and supercooled hydrogen circulation systems, the merits and drawbacks in both systems are summarized. When supercritical hydrogen circulates as the moderator, severe pressure fluctuations caused by temperature changes will occur. The pressure control system used to balance the system pressure, which consists of a heater as an active controller for thermal compensation and an accumulator as a passive volume controller, is preliminarily studied. The results may provide guidelines for design and operation of other cryogenic hydrogen system for neutron sources under construction.

  7. Kinetic simulation of neutron production in a deuterium z-pinch.

    SciTech Connect (OSTI)

    Mostrom, C. (Voss Scientific, Albuquerque, NM); Stygar, William A.; Thoma, Carsten (Voss Scientific, Albuquerque, NM); Welch, Dale Robert (Voss Scientific, Albuquerque, NM); Clark, R. E. (Voss Scientific, Albuquerque, NM); Leeper, Ramon Joe; Rose, David V. (Voss Scientific, Albuquerque, NM)

    2010-11-01T23:59:59.000Z

    We have found computationally that, at sufficiently high currents, half of the neutrons produced by a deuterium z pinch are thermonuclear in origin. Early experiments below 1-MA current found that essentially all of the neutrons produced by a deuterium pinch are not thermonuclear, but are initiated by an instability that creates beam-target neutrons. Many subsequent authors have supported this result while others have claimed that pinch neutrons are thermonuclear. To resolve this issue, we have conducted fully kinetic, collisional, and electromagnetic simulations of the complete time evolution of a deuterium pinch. We find that at 1-MA pinch currents, most of the neutrons are, indeed, beam-target in origin. At much higher current, half of the neutrons are thermonuclear and half are beam-target driven by instabilities that produce a power law fall off in the ion energy distribution function at large energy. The implications for fusion energy production with such pinches are discussed.

  8. SHARP Neutronics Expanded

    Broader source: Energy.gov [DOE]

    The SHARP neutronics module, PROTEUS, includes neutron and gamma transport solvers and cross-section processing tools as well as the capability for depletion and fuel cycle analysis.

  9. Workshop on neutron capture therapy

    SciTech Connect (OSTI)

    Fairchild, R.G.; Bond, V.P. (eds.)

    1986-01-01T23:59:59.000Z

    Potentially optimal conditions for Neutron Capture Therapy (NCT) may soon be in hand due to the anticipated development of band-pass filtered beams relatively free of fast neutron contaminations, and of broadly applicable biomolecules for boron transport such as porphyrins and monoclonal antibodies. Consequently, a number of groups in the US are now devoting their efforts to exploring NCT for clinical application. The purpose of this Workshop was to bring these groups together to exchange views on significant problems of mutual interest, and to assure a unified and effective approach to the solutions. Several areas of preclinical investigation were deemed to be necessary before it would be possible to initiate clinical studies. As neither the monomer nor the dimer of sulfhydryl boron hydride is unequivocally preferable at this time, studies on both compounds should be continued until one is proven superior.

  10. Method of using deuterium-cluster foils for an intense pulsed neutron source

    DOE Patents [OSTI]

    Miley, George H.; Yang, Xiaoling

    2013-09-03T23:59:59.000Z

    A method is provided for producing neutrons, comprising: providing a converter foil comprising deuterium clusters; focusing a laser on the foil with power and energy sufficient to cause deuteron ions to separate from the foil; and striking a surface of a target with the deuteron ions from the converter foil with energy sufficient to cause neutron production by a reaction selected from the group consisting of D-D fusion, D-T fusion, D-metal nuclear spallation, and p-metal. A further method is provided for assembling a plurality of target assemblies for a target injector to be used in the previously mentioned manner. A further method is provided for producing neutrons, comprising: splitting a laser beam into a first beam and a second beam; striking a first surface of a target with the first beam, and an opposite second surface of the target with the second beam with energy sufficient to cause neutron production.

  11. Optimizing Moderator Dimensions for Neutron Scattering at the Spallation Neutron Source

    SciTech Connect (OSTI)

    Zhao, Jinkui [ORNL; Robertson, Lee [ORNL; Herwig, Kenneth W [ORNL; Gallmeier, Franz X [ORNL; Riemer, Bernie [ORNL

    2013-01-01T23:59:59.000Z

    In this work, we investigate the effect of neutron moderator dimensions on the performance of neutron scattering instruments at the Spallation Neutron Source. In a recent study of the planned second target station at the Spallation Neutron Source (SNS) facility [1,2], we have found that the dimensions of a moderator play a significant role in determining its surface brightness. A smaller moderator may be significantly brighter for a smaller viewing area [4]. One of the immediate implications of this finding is that for modern neutron scattering instrument designs, moderator dimensions and brightness have to be incorporated as an integrated optimization parameter. Here, we establish a strategy of matching neutron scattering instruments with moderators using analytical and Monte Carlo techniques. In order to simplify our treatment, we group the instruments into two broad categories, those with natural collimation and those that use neutron guide systems. We found that the cross-sections of the sample and the neutron guide, respectively, are the deciding factors for choosing the moderator. Beam divergence plays no role as long as it is within the reach of practical constraints. Namely, the required divergence is not too large for the guide or sample to be located close enough to the moderator on an actual spallation source.

  12. IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 55, NO. 1, FEBRUARY 2008 501 Neutron Stimulated Emission Computed Tomography

    E-Print Network [OSTI]

    in the human body. NSECT uses a beam of fast neutrons that scatter inelastically from atomic nuclei in tissueIEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 55, NO. 1, FEBRUARY 2008 501 Neutron Stimulated Emission. Pedroni, and Carey E. Floyd, Jr. Abstract--Neutron stimulated emission computed tomography (NSECT

  13. For more information: Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600.

    E-Print Network [OSTI]

    For more information: Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574 Neutron Source (SNS) will be accepted via the web-based proposal system until 11:59 a.m. EST, (NOON. Information and instructions To learn more about submitting a proposal for beam time, go to http://neutrons

  14. Neutron scattering Materials research for modern life Almost all of the major changes in our society, the dramatic

    E-Print Network [OSTI]

    Crowther, Paul

    Neutron scattering Materials research for modern life #12;Almost all of the major changes in our scattering experiments, materials are exposed to intense beams of neutrons inside specialised instruments that neutron scattering science contributes to our lives. Because of the collaborative nature of modern

  15. PPPL3238 Preprint: February 1997, UC420 The Role of the Neutral Beam Fueling Profile in the Performance of the

    E-Print Network [OSTI]

    of the heating beam fueling profile shape. Ion energy confinement and neutron production are relatively confinement and neutron production can be applied to all beam heated deuterium (D) discharges in TFTR [7], limiter High­mode (H­mode) plasmas [8], and Supershots enhanced by Lithium (Li) pellet

  16. PPPL-3238 -Preprint: February 1997, UC-420 The Role of the Neutral Beam Fueling Profile in the Performance of the

    E-Print Network [OSTI]

    of the heating beam fueling profile shape. Ion energy confinement and neutron production are relatively confinement and neutron production can be applied to all beam heated deuterium (D) discharges in TFTR [7], limiter High-mode (H-mode) plasmas [8], and Supershots enhanced by Lithium (Li) pellet

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

    SciTech Connect (OSTI)

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

    1993-12-31T23:59:59.000Z

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

  18. Neutron detector using lithiated glass-scintillating particle composite

    DOE Patents [OSTI]

    Wallace, Steven (Knoxville, TN); Stephan, Andrew C. (Knoxville, TX); Dai, Sheng (Knoxville, TN); Im, Hee-Jung (Knoxville, TN)

    2009-09-01T23:59:59.000Z

    A neutron detector composed of a matrix of scintillating particles imbedded in a lithiated glass is disclosed. The neutron detector detects the neutrons by absorbing the neutron in the lithium-6 isotope which has been enriched from the natural isotopic ratio to a commercial ninety five percent. The utility of the detector is optimized by suitably selecting scintillating particle sizes in the range of the alpha and the triton. Nominal particle sizes are in the range of five to twenty five microns depending upon the specific scintillating particle selected.

  19. Nondispersive neutron focusing method beyond the critical angle of mirrors

    DOE Patents [OSTI]

    Ice, Gene E. (Oak Ridge, TN)

    2008-10-21T23:59:59.000Z

    This invention extends the Kirkpatrick-Baez (KB) mirror focusing geometry to allow nondispersive focusing of neutrons with a convergence on a sample much larger than is possible with existing KB optical schemes by establishing an array of at least three mirrors and focusing neutrons by appropriate multiple deflections via the array. The method may be utilized with supermirrors, multilayer mirrors, or total external reflection mirrors. Because high-energy x-rays behave like neutrons in their absorption and reflectivity rates, this method may be used with x-rays as well as neutrons.

  20. Position sensitive detection of neutrons in high radiation background field

    SciTech Connect (OSTI)

    Vavrik, D., E-mail: vavrik@itam.cas.cz [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, Prague (Czech Republic); Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecka 76, 190 00 Prague 9 (Czech Republic); Jakubek, J.; Pospisil, S. [Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecka 76, 190 00 Prague 9 (Czech Republic)] [Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecka 76, 190 00 Prague 9 (Czech Republic); Vacik, J. [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Rez, 250 68 Prague, Czech Republic (Czech Republic)] [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Rez, 250 68 Prague, Czech Republic (Czech Republic)

    2014-01-15T23:59:59.000Z

    We present the development of a high-resolution position sensitive device for detection of slow neutrons in the environment of extremely high ? and e{sup ?} radiation background. We make use of a planar silicon pixelated (pixel size: 55 × 55 ?m{sup 2}) spectroscopic Timepix detector adapted for neutron detection utilizing very thin {sup 10}B converter placed onto detector surface. We demonstrate that electromagnetic radiation background can be discriminated from the neutron signal utilizing the fact that each particle type produces characteristic ionization tracks in the pixelated detector. Particular tracks can be distinguished by their 2D shape (in the detector plane) and spectroscopic response using single event analysis. A Cd sheet served as thermal neutron stopper as well as intensive source of gamma rays and energetic electrons. Highly efficient discrimination was successful even at very low neutron to electromagnetic background ratio about 10{sup ?4}.

  1. Neutrostriction in Neutron stars

    E-Print Network [OSTI]

    V. K. Ignatovich

    2006-06-29T23:59:59.000Z

    It is demonstrated that not only gravity, but also neutrostriction forces due to optical potential created by coherent elastic neutron-neutron scattering can hold a neutron star together. The latter forces can be stronger than gravitational ones. The effect of these forces on mass, radius and structure of the neutron star is estimated.

  2. Neutron reflecting supermirror structure

    DOE Patents [OSTI]

    Wood, James L. (Drayton Plains, MI)

    1992-01-01T23:59:59.000Z

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. One layer of each set of bilayers consist of titanium, and the second layer of each set of bilayers consist of an alloy of nickel with carbon interstitially present in the nickel alloy.

  3. Dosimetry in Thermal Neutron Irradiation Facility at BMRR

    SciTech Connect (OSTI)

    Hu, J. P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Holden, N. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Reciniello, R. N.

    2014-05-23T23:59:59.000Z

    Radiation dosimetry for Neutron Capture Therapy (NCT) has been performed since 1959 at Thermal Neutron Irradiation Facility (TNIF) of the three-megawatt light-water cooled Brookhaven Medical Research Reactor (BMRR). In the early 1990s when more effective drug carriers were developed for NCT, in which the eye melanoma and brain tumors in rats were irradiated in situ, extensive clinical trials of small animals began using a focused thermal neutron beam. To improve the dosimetry at irradiation facility, a series of innovative designs and major modifications made to enhance the beam intensity and to ease the experimental sampling at BMRR were performed; including (1) in-core fuel addition to increase source strength and balance flux of neutrons towards two ports, (2) out of core moderator remodeling, done by replacing thicker D2O tanks at graphite-shutter interfacial areas, to expedite neutron thermalization, (3) beam shutter upgrade to reduce strayed neutrons and gamma dose, (4) beam collimator redesign to optimize the beam flux versus dose for animal treatment, (5) beam port shielding installation around the shutter opening area (lithium-6 enriched polyester-resin in boxes, attached with polyethylene plates) to reduce prompt gamma and fast neutron doses, (6) sample holder repositioning to optimize angle versus distance for a single organ or whole body irradiation, and (7) holder wall buildup with neutron reflector materials to increase dose and dose rate from scattered thermal neutrons. During the facility upgrade, reactor dosimetry was conducted using thermoluminescent dosimeters TLD for gamma dose estimate, using ion chambers to confirm fast neutron and gamma dose rate, and by the activation of gold-foils with and without cadmium-covers, for fast and thermal neutron flux determination. Based on the combined effect from the size and depth of tumor cells and the location and geometry of dosimeters, the measured flux from cadmium-difference method was 4 - 7 % lower than the statistical mean derived from the Monte-Carlo modeling (5% uncertainty). The dose rate measured by ion chambers was 6 - 10 % lower than the output tallies (7% uncertainty). The detailed dosimetry that was performed at the TNIF for the NCT will be described.

  4. Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression

    DOE Patents [OSTI]

    Lasche, G.P.

    1983-09-29T23:59:59.000Z

    The invention is a laser or particle-beam-driven fusion reactor system which takes maximum advantage of both the very short pulsed nature of the energy release of inertial confinement fusion (ICF) and the very small volumes within which the thermonuclear burn takes place. The pulsed nature of ICF permits dynamic direct energy conversion schemes such as magnetohydrodynamic (MHD) generation and magnetic flux compression; the small volumes permit very compact blanket geometries. By fully exploiting these characteristics of ICF, it is possible to design a fusion reactor with exceptionally high power density, high net electric efficiency, and low neutron-induced radioactivity. The invention includes a compact blanket design and method and apparatus for obtaining energy utilizing the compact blanket.

  5. Imaging with Scattered Neutrons

    E-Print Network [OSTI]

    H. Ballhausen; H. Abele; R. Gaehler; M. Trapp; A. Van Overberghe

    2006-10-30T23:59:59.000Z

    We describe a novel experimental technique for neutron imaging with scattered neutrons. These scattered neutrons are of interest for condensed matter physics, because they permit to reveal the local distribution of incoherent and coherent scattering within a sample. In contrast to standard attenuation based imaging, scattered neutron imaging distinguishes between the scattering cross section and the total attenuation cross section including absorption. First successful low-noise millimeter-resolution images by scattered neutron radiography and tomography are presented.

  6. Deuterium density profile determination at JET using a neutron camera and a neutron spectrometer

    SciTech Connect (OSTI)

    Eriksson, J., E-mail: jacob.eriksson@physics.uu.se; Castegnetti, G.; Conroy, S.; Ericsson, G.; Hellesen, C. [EURATOM-VR, Department of Physics and Astronomy, Uppsala University (Sweden); Giacomelli, L. [Department of Physics, Università degli Studi di Milano-Bicocca, Milano (Italy); EURATOM-CCFE Fusion Association, Culham Science Centre, Abingdon (United Kingdom)

    2014-11-15T23:59:59.000Z

    In this work we estimate the fuel ion density profile in deuterium plasmas at JET, using the JET neutron camera, the neutron time-of-flight spectrometer TOFOR, and fusion reactivities modeled by the transport code TRANSP. The framework has been tested using synthetic data, which showed that the density profile could be reconstructed with an average accuracy of the order of 10 %. The method has also been applied to neutron measurements from a neutral beam heated JET discharge, which gave n{sub d}/n{sub e} ? 0.6 ± 0.3 in the plasma core and n{sub d}/n{sub e} ? 0.4 ± 0.3 towards the edge. Correction factors for detector efficiencies, neutron attenuation, and back-scattering are not yet included in the analysis; future work will aim at refining the estimated density.

  7. Phys. Med. Bid. 40 (1995) 757-767. Printed in the UK An expressionfor the RBE of neutrons as afunctionof neutron

    E-Print Network [OSTI]

    ., which wn be used to design neutron Sources for BNCT. In m earlier calculation of a neutron RBE beams at the Brookhaven Medical Research Reactor (BMRR) and at Petten (Gavin 1993, Siefert et a1 1993;758 these components is often calculated separately (Nigg 1994). and often inconsistent RBES are individually applied

  8. Measurements of prompt gamma-rays from fast-neutron induced fission with the LICORNE directional neutron source

    E-Print Network [OSTI]

    Wilson, J N; Halipre, P; Oberstedt, S; Oberstedt, A

    2014-01-01T23:59:59.000Z

    At the IPN Orsay we have developed a unique, directional, fast neutron source called LICORNE, intended initially to facilitate prompt fission gamma measurements. The ability of the IPN Orsay tandem accelerator to produce intense beams of $^7$Li is exploited to produce quasi-monoenergetic neutrons between 0.5 - 4 MeV using the p($^7$Li,$^7$Be)n inverse reaction. The available fluxes of up to 7 × 10$^7$ neutrons/second/steradian for the thickest hydrogen-rich targets are comparable to similar installations, but with two added advantages: (i) The kinematic focusing produces a natural neutron beam collimation which allows placement of gamma detectors adjacent to the irradiated sample unimpeded by source neutrons. (ii) The background of scattered neutrons in the experimental hall is drastically reduced. The dedicated neutron converter was commissioned in June 2013. Some preliminary results from the first experiment using the LICORNE neutron source at the IPN Orsay are presented. Prompt fission gamma rays from fas...

  9. Proposal of thermal neutron flux monitors based on vibrating wire

    E-Print Network [OSTI]

    Arutunian, S G; Chung, M; Harutyunyan, G S; Lazareva, E G

    2015-01-01T23:59:59.000Z

    Two types of neutron monitors with fine spatial resolution are proposed based on vibrating wire. In the first type, neutrons interact with the vibrating wire, heat it, and lead to the change of natural frequency, which can be precisely measured. To increase the heat deposition during the neutron scattering, use of gadolinium layer which has the highest thermal neutron capture cross section among all elements is proposed. The second type of the monitor uses vibrating wire as a resonant target. Besides the measurement of beam profile according to the average signal, the differential signal synchronized with the wire oscillations defines the gradient of beam profile. Spatial resolution of the monitor is defined by the diameter of the wire.

  10. Accelerator beam profile analyzer

    DOE Patents [OSTI]

    Godel, Julius B. (Bayport, NY); Guillaume, Marcel (Grivegnee, BE); Lambrecht, Richard M. (East Quogue, NY); Withnell, Ronald (East Setauket, NY)

    1976-01-01T23:59:59.000Z

    A beam profile analyzer employing sector or quadrant plates each servo controlled to outline the edge of a beam.

  11. Advanced Neutron Source (ANS) Project Progress report, FY 1991

    SciTech Connect (OSTI)

    Campbell, J.H. [ed.] [Oak Ridge National Lab., TN (United States); Selby, D.L.; Harrington, R.M. [Oak Ridge National Lab., TN (United States); Thompson, P.B. [Martin Marietta Energy Systems, Inc., (United States). Engineering Division

    1992-01-01T23:59:59.000Z

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I & C Research and Development; Design; and Safety.

  12. Advanced Neutron Source (ANS) Project Progress report, FY 1991

    SciTech Connect (OSTI)

    Campbell, J.H. (ed.) (Oak Ridge National Lab., TN (United States)); Selby, D.L.; Harrington, R.M. (Oak Ridge National Lab., TN (United States)); Thompson, P.B. (Martin Marietta Energy Systems, Inc., (United States). Engineering Division)

    1992-01-01T23:59:59.000Z

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I C Research and Development; Design; and Safety.

  13. Optimizing moderator dimensions for neutron scattering at the spallation neutron source

    SciTech Connect (OSTI)

    Zhao, J. K.; Robertson, J. L.; Herwig, Kenneth W.; Gallmeier, Franz X.; Riemer, Bernard W. [Instrument and Source Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Instrument and Source Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2013-12-15T23:59:59.000Z

    In this work, we investigate the effect of neutron moderator dimensions on the performance of neutron scattering instruments at the Spallation Neutron Source (SNS). In a recent study of the planned second target station at the SNS facility, we have found that the dimensions of a moderator play a significant role in determining its surface brightness. A smaller moderator may be significantly brighter over a smaller viewing area. One of the immediate implications of this finding is that for modern neutron scattering instrument designs, moderator dimensions and brightness have to be incorporated as an integrated optimization parameter. Here, we establish a strategy of matching neutron scattering instruments with moderators using analytical and Monte Carlo techniques. In order to simplify our treatment, we group the instruments into two broad categories: those with natural collimation and those that use neutron guide systems. For instruments using natural collimation, the optimal moderator selection depends on the size of the moderator, the sample, and the moderator brightness. The desired beam divergence only plays a role in determining the distance between sample and moderator. For instruments using neutron optical systems, the smallest moderator available that is larger than the entrance dimension of the closest optical element will perform the best (assuming, as is the case here that smaller moderators are brighter)

  14. Design of a boron neutron capture enhanced fast neutron therapy assembly

    SciTech Connect (OSTI)

    Wang, Zhonglu; /Georgia Tech

    2006-08-01T23:59:59.000Z

    The use of boron neutron capture to boost tumor dose in fast neutron therapy has been investigated at several fast neutron therapy centers worldwide. This treatment is termed boron neutron capture enhanced fast neutron therapy (BNCEFNT). It is a combination of boron neutron capture therapy (BNCT) and fast neutron therapy (FNT). It is believed that BNCEFNT may be useful in the treatment of some radioresistant brain tumors, such as glioblastoma multiform (GBM). A boron neutron capture enhanced fast neutron therapy assembly has been designed for the Fermilab Neutron Therapy Facility (NTF). This assembly uses a tungsten filter and collimator near the patient's head, with a graphite reflector surrounding the head to significantly increase the dose due to boron neutron capture reactions. The assembly was designed using Monte Carlo radiation transport code MCNP version 5 for a standard 20x20 cm{sup 2} treatment beam. The calculated boron dose enhancement at 5.7-cm depth in a water-filled head phantom in the assembly with a 5x5 cm{sup 2} collimation was 21.9% per 100-ppm {sup 10}B for a 5.0-cm tungsten filter and 29.8% for a 8.5-cm tungsten filter. The corresponding dose rate for the 5.0-cm and 8.5-cm thick filters were 0.221 and 0.127 Gy/min, respectively; about 48.5% and 27.9% of the dose rate of the standard 10x10 cm{sup 2} fast neutron treatment beam. To validate the design calculations, a simplified BNCEFNT assembly was built using four lead bricks to form a 5x5 cm{sup 2} collimator. Five 1.0-cm thick 20x20 cm{sup 2} tungsten plates were used to obtain different filter thicknesses and graphite bricks/blocks were used to form a reflector. Measurements of the dose enhancement of the simplified assembly in a water-filled head phantom were performed using a pair of tissue-equivalent ion chambers. One of the ion chambers is loaded with 1000-ppm natural boron (184-ppm {sup 10}B) to measure dose due to boron neutron capture. The measured dose enhancement at 5.0-cm depth in the head phantom for the 5.0-cm thick tungsten filter is (16.6 {+-} 1.8)%, which agrees well with the MCNP simulation of the simplified BNCEFNT assembly, (16.4 {+-} 0.5)%. The error in the calculated dose enhancement only considers the statistical uncertainties. The total dose rate measured at 5.0-cm depth using the non-borated ion chamber is (0.765 {+-} 0.076) Gy/MU, about 61% of the fast neutron standard dose rate (1.255Gy/MU) at 5.0-cm depth for the standard 10x10 cm{sup 2} treatment beam. The increased doses to other organs due to the use of the BNCEFNT assembly were calculated using MCNP5 and a MIRD phantom. The activities of the activation products produced in the BNCEFNT assembly after neutron beam delivery were computed. The photon ambient dose rate due to the radioactive activation products was also estimated.

  15. Synthesis of transactinide nuclei in cold fusion reactions using radioative beams

    E-Print Network [OSTI]

    Smolanczuk, Robert

    2009-01-01T23:59:59.000Z

    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.

  16. Synthesis of transactinide nuclei in cold fusion reactions using radioactive beams

    SciTech Connect (OSTI)

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

    2010-06-15T23:59:59.000Z

    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.

  17. Synthesis of transactinide nuclei in cold fusion reactions using radioative beams

    E-Print Network [OSTI]

    Robert Smolanczuk

    2009-12-04T23:59:59.000Z

    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.

  18. Radiochemical Transformation of High Pressure Methane under Gamma, Electron, and Neutron Irradiation

    E-Print Network [OSTI]

    Clemens, Jeffrey Tyler

    2014-05-01T23:59:59.000Z

    The chemical effects of irradiation on high pressure methane and noble gas mixtures were investigated using gamma, electron beam, and neutron irradiation sources. The gamma source used was the La-140 source from the Nuclear Science Center (NSC...

  19. Neutron streak camera

    DOE Patents [OSTI]

    Wang, C.L.

    1981-05-14T23:59:59.000Z

    Apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon.

  20. Layered semiconductor neutron detectors

    DOE Patents [OSTI]

    Mao, Samuel S; Perry, Dale L

    2013-12-10T23:59:59.000Z

    Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

  1. Neutron streak camera

    DOE Patents [OSTI]

    Wang, C.L.

    1983-09-13T23:59:59.000Z

    Disclosed is an apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon. 4 figs.

  2. Observations of Space Charge effects in the Spallation Neutron Source Accumulator Ring

    SciTech Connect (OSTI)

    Potts III, Robert E [ORNL] [ORNL; Cousineau, Sarah M [ORNL] [ORNL; Holmes, Jeffrey A [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    The Spallation Neutron Source accumulator ring was designed to allow independent control of the transverse beam distribution in each plane. However, at high beam intensities, nonlinear space charge forces can strongly influence the final beam distribution and compromise our ability to independently control the transverse distributions. In this study we investigate the evolution of the beam at intensities of up to ~8x10^13 ppp through both simulation and experiment. Specifically, we analyze the evolution of the beam distribution for beams with different transverse aspect ratios and tune splits. We present preliminary results of simulations of our experiments.

  3. Commissioning of the new high-intensity ultracold neutron source at the Paul Scherrer Institut

    E-Print Network [OSTI]

    Bernhard Lauss

    2010-11-17T23:59:59.000Z

    Commissioning of the new high-intensity ultracold neutron (UCN) source at the Paul Scherrer Institut (PSI) has started in 2009. The design goal of this new generation high intensity UCN source is to surpass by a factor of ~100 the current ultracold neutron densities available for fundamental physics research, with the greatest thrust coming from the search for a neutron electric dipole moment. The PSI UCN source is based on neutron production via proton induced lead spallation, followed by neutron thermalization in heavy water and neutron cooling in a solid deuterium crystal to cold and ultracold energies. A successful beam test with up to 2 mA proton beam on the spallation target was conducted recently. Most source components are installed, others being finally mounted. The installation is on the track for the first cool-down and UCN production in 2010.

  4. {Beta}-delayed neutron decay of {sup 17}C and {sup 18}C

    SciTech Connect (OSTI)

    Scheller, K.W.; Goerres, J.; Vouzoukas, S.; Wiescher, M. [Univ. of Notre Dame, South Bend, IN (United States)] [and others

    1993-10-01T23:59:59.000Z

    The {Beta}-delayed neutron decay of {sup 17}C and {sup 18}C has bear measured to investigate neutron-unbound levels in {sup 17}N and {sup 19}N. Levels of interest in {sup 17}N and {sup 18}N are those near the neutron threshold which may play a role in a astrophysical reprocess during an inhomogeneous Big Bang. Radioactive ion beaming of {sup 17}C and {sup 18}C were produced by beam fragmentation at the NSCL MSU. Ions were implanted in a plastic scintillator which served as a start detector for a time-of-flight measurement. Neutrons were detected in the MSU neutron detector array. Several neutron groups have been observed and the results will be discussed.

  5. Enhanced Fusion-Evaporation Cross Sections in Neutron-Rich $^{132}$Sn on $^{64}$Ni

    E-Print Network [OSTI]

    J. F. Liang; D. Shapira; C. J. Gross; J. R. Beene; J. D. Bierman; A. Galindo-Uribarri; J. Gomez del Campo; P. A. Hausladen; Y. Larochelle; W. Loveland; P. E. Mueller; D. Peterson; D. C. Radford; D. W. Stracener; R. L. Varner

    2003-04-02T23:59:59.000Z

    Evaporation residue cross sections have been measured with neutron-rich radioactive $^{132}$Sn beams on $^{64}$Ni in the vicinity of the Coulomb barrier. The average beam intensity was $2\\times 10^{4}$ particles per second and the smallest cross section measured was less than 5 mb. Large subbarrier fusion enhancement was observed. Coupled-channels calculations taking into account inelastic excitation and neutron transfer underpredict the measured cross sections below the barrier.

  6. Los Alamos Using Neutrons to Stop Nuclear Smugglers

    SciTech Connect (OSTI)

    Favalli, Andrea; Swinhoe, Martyn

    2013-06-03T23:59:59.000Z

    Los Alamos National Laboratory researchers have successfully demonstrated for the first time that laser-generated neutrons can be enlisted as a useful tool in the War on Terror. The international research team used the short-pulse laser at Los Alamos's TRIDENT facility to generate a neutron beam with novel characteristics that interrogated a closed container to confirm the presence and quantity of nuclear material inside. The successful experiment paves the way for creation of a table-top-sized or truck-mounted neutron generator that could be installed at strategic locations worldwide to thwart smugglers trafficking in nuclear materials.

  7. Los Alamos Using Neutrons to Stop Nuclear Smugglers

    ScienceCinema (OSTI)

    Favalli, Andrea; Swinhoe, Martyn

    2014-06-02T23:59:59.000Z

    Los Alamos National Laboratory researchers have successfully demonstrated for the first time that laser-generated neutrons can be enlisted as a useful tool in the War on Terror. The international research team used the short-pulse laser at Los Alamos's TRIDENT facility to generate a neutron beam with novel characteristics that interrogated a closed container to confirm the presence and quantity of nuclear material inside. The successful experiment paves the way for creation of a table-top-sized or truck-mounted neutron generator that could be installed at strategic locations worldwide to thwart smugglers trafficking in nuclear materials.

  8. Time dependence of delayed neutron emission for fissionable isotope identification

    SciTech Connect (OSTI)

    Kinlaw, M.T.; Hunt, A.W. [Idaho Accelerator Center, Idaho State University, Pocatello, Idaho 83209-8263 (United States); Department of Physics, Idaho State University, Pocatello, Idaho 83209-8106 (United States)

    2005-06-20T23:59:59.000Z

    The time dependence of delayed neutron emission was examined as a method of fissionable isotope identification. A pulsed bremsstrahlung photon beam was used to induce photofission reactions in {sup 238}U, {sup 232}Th, and {sup 239}Pu targets. The resulting delayed neutron emission was recorded between irradiating pulses and is a well-known technique for fissionable material detection. Monitoring the decay of delayed neutron emission between irradiating pulses demonstrates the ability to not only detect the presence of fissionable materials, but also to identify which fissionable isotope is present.

  9. Beam Status

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMForms About Batteries Batteries An error occurred. TryRing CurrentBeam

  10. Beam History

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumniComplex historian ...BESFor Users LiveBattling birdBeam

  11. Beam History

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumniComplex historian ...BESFor Users LiveBattlingBeam

  12. Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy

    DOE Patents [OSTI]

    Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

    1997-03-18T23:59:59.000Z

    A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

  13. Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy

    DOE Patents [OSTI]

    Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

    1995-10-03T23:59:59.000Z

    A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

  14. Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy

    DOE Patents [OSTI]

    Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

    1997-08-05T23:59:59.000Z

    A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized. by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

  15. Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy

    DOE Patents [OSTI]

    Miura, M.; Slatkin, D.N.

    1997-08-05T23:59:59.000Z

    A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na{sub 4}B{sub 12}I{sub 11}SSB{sub 12}I{sub 11}, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy. 1 fig.

  16. Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy

    DOE Patents [OSTI]

    Miura, M.; Slatkin, D.N.

    1997-03-18T23:59:59.000Z

    A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na{sub 4}B{sub 12}I{sub 11}SSB{sub 12}I{sub 11}, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy. 1 fig.

  17. Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy

    DOE Patents [OSTI]

    Miura, M.; Slatkin, D.N.

    1995-10-03T23:59:59.000Z

    A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na{sub 4}B{sub 12}I{sub 11}SSB{sub 12}I{sub 11}, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy. 1 fig.

  18. Beam geometry selection using sequential beam addition

    SciTech Connect (OSTI)

    Popple, Richard A., E-mail: rpopple@uabmc.edu; Brezovich, Ivan A.; Fiveash, John B. [Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294 (United States)] [Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: The selection of optimal beam geometry has been of interest since the inception of conformal radiotherapy. The authors report on sequential beam addition, a simple beam geometry selection method, for intensity modulated radiation therapy. Methods: The sequential beam addition algorithm (SBA) requires definition of an objective function (score) and a set of candidate beam geometries (pool). In the first iteration, the optimal score is determined for each beam in the pool and the beam with the best score selected. In the next iteration, the optimal score is calculated for each beam remaining in the pool combined with the beam selected in the first iteration, and the best scoring beam is selected. The process is repeated until the desired number of beams is reached. The authors selected three treatment sites, breast, lung, and brain, and determined beam arrangements for up to 11 beams from a pool comprised of 25 equiangular transverse beams. For the brain, arrangements were additionally selected from a pool of 22 noncoplanar beams. Scores were determined for geometries comprised equiangular transverse beams (EQA), as well as two tangential beams for the breast case. Results: In all cases, SBA resulted in scores superior to EQA. The breast case had the strongest dependence on beam geometry, for which only the 7-beam EQA geometry had a score better than the two tangential beams, whereas all SBA geometries with more than two beams were superior. In the lung case, EQA and SBA scores monotonically improved with increasing number of beams; however, SBA required fewer beams to achieve scores equivalent to EQA. For the brain case, SBA with a coplanar pool was equivalent to EQA, while the noncoplanar pool resulted in slightly better scores; however, the dose-volume histograms demonstrated that the differences were not clinically significant. Conclusions: For situations in which beam geometry has a significant effect on the objective function, SBA can identify arrangements equivalent to equiangular geometries but using fewer beams. Furthermore, SBA provides the value of the objective function as the number of beams is increased, allowing the planner to select the minimal beam number that achieves the clinical goals. The method is simple to implement and could readily be incorporated into an existing optimization system.

  19. Astrophysics experiments with radioactive beams at ATLAS

    SciTech Connect (OSTI)

    Back, B. B.; Clark, J. A.; Pardo, R. C.; Rehm, K. E., E-mail: rehm@anl.gov; Savard, G. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)] [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2014-04-15T23:59:59.000Z

    Reactions involving short-lived nuclei play an important role in nuclear astrophysics, especially in explosive scenarios which occur in novae, supernovae or X-ray bursts. This article describes the nuclear astrophysics program with radioactive ion beams at the ATLAS accelerator at Argonne National Laboratory. The CARIBU facility as well as recent improvements for the in-flight technique are discussed. New detectors which are important for studies of the rapid proton or the rapid neutron-capture processes are described. At the end we briefly mention plans for future upgrades to enhance the intensity, purity and the range of in-flight and CARIBU beams.

  20. Ultrafast neutron detector

    DOE Patents [OSTI]

    Wang, C.L.

    1985-06-19T23:59:59.000Z

    A neutron detector of very high temporal resolution is described. It may be used to measure distributions of neutrons produced by fusion reactions that persist for times as short as about 50 picoseconds.

  1. Neutron dose equivalent meter

    DOE Patents [OSTI]

    Olsher, Richard H. (Los Alamos, NM); Hsu, Hsiao-Hua (Los Alamos, NM); Casson, William H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM); Kleck, Jeffrey H. (Menlo Park, CA); Beverding, Anthony (Foster City, CA)

    1996-01-01T23:59:59.000Z

    A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.

  2. Incident spectrum determination for time-of-flight neutron powder diffraction data analysis.

    SciTech Connect (OSTI)

    Hodges, J. P.

    1998-08-27T23:59:59.000Z

    Accurate characterization of the incident neutron spectrum is an important requirement for precise Rietveld analysis of time-of-flight powder neutron diffraction data. Without an accurate incident spectrum the calculated model for the measured relative intensities of individual Bragg reflections will possess systematic errors. We describe a method for obtaining an accurate numerical incident spectrum using data from a transmitted beam monitor.

  3. Accelerator-based neutron source using a cold deuterium target with degenerate electrons

    SciTech Connect (OSTI)

    Phillips, R. E.; Ordonez, C. A. [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)] [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)

    2013-07-15T23:59:59.000Z

    A neutron generator is considered in which a beam of tritons is incident on a hypothetical cold deuterium target with degenerate electrons. The energy efficiency of neutron generation is found to increase substantially with electron density. Recent reports of potential targets are discussed.

  4. Simulation of a D-T Neutron Source for Neutron Scattering Experiments

    E-Print Network [OSTI]

    Lou, T.P.; Ludewigt, B.A.; Vujic, J.L.; Leung, K.-N.

    2003-01-01T23:59:59.000Z

    T Neutron Source for Neutron Scattering Experiments T.P. Louor cold neutrons for neutron scattering experiments. Thisto simulate a neutron scattering setup and to estimate

  5. Efficiency determination of resistive plate chambers for fast quasi-monoenergetic neutrons

    E-Print Network [OSTI]

    M. Röder; Z. Elekes; T. Aumann; D. Bemmerer; K. Boretzky; C. Caesar; T. E. Cowan; J. Hehner; M. Heil; M. Kempe; V. Maroussov; O. Nusair; A. V. Prokofiev; R. Reifarth; M. Sobiella; D. Stach; A. Wagner; D. Yakorev; A. Zilges; K. Zuber

    2014-07-10T23:59:59.000Z

    Composite detectors made of stainless steel converters and multigap resistive plate chambers have been irradiated with quasi-monoenergetic neutrons with a peak energy of 175MeV. The neutron detection efficiency has been determined using two different methods. The data are in agreement with the output of Monte Carlo simulations. The simulations are then extended to study the response of a hypothetical array made of these detectors to energetic neutrons from a radioactive ion beam experiment.

  6. {beta}-delayed neutron decay in {sup 17}B and {sup 19}C

    SciTech Connect (OSTI)

    Raimann, G. [Department of Physics, The Ohio State University, Columbus, Ohio 43210 (United States); Ozawa, A. [The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-01 (Japan); Boyd, R.N. [Department of Physics, The Ohio State University, Columbus, Ohio 43210 (United States)]|[Department of Astronomy, The Ohio State University, Columbus, Ohio 43210 (United States); Chloupek, F.R. [Department of Physics, The Ohio State University, Columbus, Ohio 43210 (United States); Fujimaki, M. [The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-01 (Japan); Kimura, K. [Nagasaki Institute of Applied Science, Nagasaki, Nagasaki 851-01 (Japan); Kobayashi, T. [The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-01 (Japan); Kolata, J.J. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Kubono, S. [Institute of Nuclear Study, University of Tokyo, Tanashi, Tokyo 188 (Japan); Tanihata, I.; Watanabe, Y.; Yoshida, K. [The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-01 (Japan)

    1995-02-05T23:59:59.000Z

    The {beta}-delayed neutron decays of {sup 17}B and {sup 19}C were studied using radioactive ion beams. The neutron energies, measured via time-of-flight, give information on states above the neutron decay threshold in {sup 17}C and {sup 19}N, respectively. These low lying states are of possible interest for Big Bang nucleosynthesis. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  7. Neutrons for Catalysis: A Workshop on Neutron Scattering Techniques for Studies in Catalysis

    SciTech Connect (OSTI)

    Overbury, Steven {Steve} H [ORNL; Coates, Leighton [ORNL; Herwig, Kenneth W [ORNL; Kidder, Michelle [ORNL

    2011-10-01T23:59:59.000Z

    This report summarizes the Workshop on Neutron Scattering Techniques for Studies in Catalysis, held at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) on September 16 and 17, 2010. The goal of the Workshop was to bring experts in heterogeneous catalysis and biocatalysis together with neutron scattering experimenters to identify ways to attack new problems, especially Grand Challenge problems in catalysis, using neutron scattering. The Workshop locale was motivated by the neutron capabilities at ORNL, including the High Flux Isotope Reactor (HFIR) and the new and developing instrumentation at the SNS. Approximately 90 researchers met for 1 1/2 days with oral presentations and breakout sessions. Oral presentations were divided into five topical sessions aimed at a discussion of Grand Challenge problems in catalysis, dynamics studies, structure characterization, biocatalysis, and computational methods. Eleven internationally known invited experts spoke in these sessions. The Workshop was intended both to educate catalyst experts about the methods and possibilities of neutron methods and to educate the neutron community about the methods and scientific challenges in catalysis. Above all, it was intended to inspire new research ideas among the attendees. All attendees were asked to participate in one or more of three breakout sessions to share ideas and propose new experiments that could be performed using the ORNL neutron facilities. The Workshop was expected to lead to proposals for beam time at either the HFIR or the SNS; therefore, it was expected that each breakout session would identify a few experiments or proof-of-principle experiments and a leader who would pursue a proposal after the Workshop. Also, a refereed review article will be submitted to a prominent journal to present research and ideas illustrating the benefits and possibilities of neutron methods for catalysis research.

  8. Avista Utilities- Net Metering

    Broader source: Energy.gov [DOE]

    Idaho does not have a statewide net-metering policy. However, each of the state's three investor-owned utilities -- Avista Utilities, Idaho Power and Rocky Mountain Power -- has developed a net...

  9. Mississippi Public Utility Act

    Broader source: Energy.gov [DOE]

    The Mississippi Public Utility Act is relevant to any project that plans to generate energy. It requires that a utility must first obtain a Certificate of Public Convenience and Necessity (CPCN)...

  10. INCREASED UNDERSTANDING OF BEAM LOSSES FROM THE SNS LINAC PROTON EXPERIMENT

    SciTech Connect (OSTI)

    Aleksandrov, Alexander V [ORNL] [ORNL; Shishlo, Andrei P [ORNL] [ORNL; Plum, Michael A [ORNL] [ORNL; Lebedev, Valerie [FNAL] [FNAL; Laface, Emanuele [ESS] [ESS; Galambos, John D [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    Beam loss is a major concern for high power hadron accelerators such as the Spallation Neutron Source (SNS). An unexpected beam loss in the SNS superconducting linac (SCL) was observed during the power ramp up and early operation. Intra-beam-stripping (IBS) loss, in which interactions between H- particles within the accelerated bunch strip the outermost electron, was recently identified as a possible cause of the beam loss. A set of experiments using proton beam acceleration in the SNS linac was conducted, which supports IBS as the primary beam loss mechanism in the SNS SCL.

  11. Bouncing Neutrons and the Neutron Centrifuge

    E-Print Network [OSTI]

    P. J. S. Watson

    2003-02-26T23:59:59.000Z

    The recent observation of the quantum state of the neutron bouncing freely under gravity allows some novel experiments. A method of purifying the ground state is given, and possible applications to the measurement of the electric dipole moment of the neutron and the short distance behaviour of gravity are discussed.

  12. Electrical utilities relay settings

    SciTech Connect (OSTI)

    HACHE, J.M.

    1999-02-24T23:59:59.000Z

    This document contains the Hanford transmission and distribution system relay settings that are under the control of Electrical Utilities.

  13. GSA- Utility Interconnection Agreements

    Broader source: Energy.gov [DOE]

    Presentation given at the Spring 2010 Federal Utility Partnership Working Group (FUPWG) meeting in Providence, Rhode Island.

  14. Arsenic activation neutron detector

    DOE Patents [OSTI]

    Jacobs, E.L.

    1980-01-28T23:59:59.000Z

    A detector of bursts of neutrons from a deuterium-deuteron reaction includes a quantity of arsenic adjacent a gamma detector such as a scintillator and photomultiplier tube. The arsenic is activated by the 2.5-MeV neutrons to release gamma radiation which is detected to give a quantitative representation of detected neutrons.

  15. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    International Conference onFly Ash Disposal and Utilization,onJanuary 20-22, 1998, New Delhi, India. COAL ASH and Applied Science THE UNIVERSITY OF WISCONSIN - MILWAUKEE #12;COAL ASH GENERATIONANDUTILIZATION: A REVIEW and utilization of coal ash in many parts of the world. The utilization potential for coal ash generated from

  16. Non-Destructive Spent Fuel Characterization with Semi-Conducting Gallium Arsinde Neutron Imaging Arrays

    SciTech Connect (OSTI)

    Douglas S. McGregor; Holly K. Gersch; Jeffrey D. Sanders; John C. Lee; Mark D. Hammig; Michael R. Hartman; Yong Hong Yang; Raymond T. Klann; Brian Van Der Elzen; John T. Lindsay; Philip A. Simpson

    2002-01-30T23:59:59.000Z

    High resistivity bulk grown GaAs has been used to produce thermal neutron imaging devices for use in neutron radiography and characterizing burnup in spent fuel. The basic scheme utilizes a portable Sb/Be source for monoenergetic (24 keV) neutron radiation source coupled to an Fe filter with a radiation hard B-coated pixellated GaAs detector array as the primary neutron detector. The coated neutron detectors have been tested for efficiency and radiation hardness in order to determine their fitness for the harsh environments imposed by spent fuel. Theoretical and experimental results are presented, showing detector radiation hardness, expected detection efficiency and the spatial resolution from such a scheme. A variety of advanced neutron detector designs have been explored, with experimental results achieving 13% thermal neutron detection efficiency while projecting the possibility of over 30% thermal neutron detection efficiency.

  17. Method for changing the cross section of a laser beam

    DOE Patents [OSTI]

    Sweatt, William C. (Albuquerque, NM); Seppala, Lynn (Livermore, CA)

    1995-01-01T23:59:59.000Z

    A technique is disclosed herein in which a circular optical beam, for example a copper vapor laser (CVL) beam, is converted to a beam having a profile other than circular, e.g. square or triangular. This is accomplished by utilizing a single optical mirror having a reflecting surface designed in accordance with a specifically derived formula in order to make the necessary transformation, without any substantial light loss and without changing substantially the intensity profile of the circular beam which has a substantially uniform intensity profile. In this way, the output beam can be readily directed into the dye cell of a dye laser.

  18. Method for changing the cross section of a laser beam

    DOE Patents [OSTI]

    Sweatt, W.C.; Seppala, L.

    1995-12-05T23:59:59.000Z

    A technique is disclosed herein in which a circular optical beam, for example a copper vapor laser (CVL) beam, is converted to a beam having a profile other than circular, e.g. square or triangular. This is accomplished by utilizing a single optical mirror having a reflecting surface designed in accordance with a specifically derived formula in order to make the necessary transformation, without any substantial light loss and without changing substantially the intensity profile of the circular beam which has a substantially uniform intensity profile. In this way, the output beam can be readily directed into the dye cell of a dye laser. 4 figs.

  19. Crystal Driven Neutron Source: A New Paradigm for Miniature Neutron Sources

    SciTech Connect (OSTI)

    Tang, V; Morse, J; Meyer, G; Falabella, S; Guethlein, G; Kerr, P; Park, H G; Rusnak, B; Sampayan, S; Schmid, G; Spadaccini, C; Wang, L

    2008-08-08T23:59:59.000Z

    Neutron interrogation techniques have specific advantages for detection of hidden, shielded, or buried threats over other detection modalities in that neutrons readily penetrate most materials providing backscattered gammas indicative of the elemental composition of the potential threat. Such techniques have broad application to military and homeland security needs. Present neutron sources and interrogation systems are expensive and relatively bulky, thereby making widespread use of this technique impractical. Development of a compact, high intensity crystal driven neutron source is described. The crystal driven neutron source approach has been previously demonstrated using pyroelectric crystals that generate extremely high voltages when thermal cycled [1-4]. Placement of a sharpened needle on the positively polarized surface of the pyroelectric crystal results in sufficient field intensification to field ionize background deuterium molecules in a test chamber, and subsequently accelerate the ions to energies in excess of {approx}100 keV, sufficient for either D-D or D-T fusion reactions with appropriate target materials. Further increase in ion beam current can be achieved through optimization of crystal thermal ramping, ion source and crystal accelerator configuration. The advantage of such a system is the compact size along with elimination of large, high voltage power supplies. A novel implementation discussed incorporates an independently controlled ion source in order to provide pulsed neutron operation having microsecond pulse width.

  20. Observation of neutron multiplication by delayed neutrons in {sup 237}Np and {sup 235}U

    SciTech Connect (OSTI)

    Hollas, C.L.; Goulding, C.A.; Moss, C.E.; Myers, W.L.

    2000-07-01T23:59:59.000Z

    The authors have applied the method using delayed neutrons developed for the investigation of highly enriched uranium (HEU) systems to investigate {sup 237}Np. This method uses an external radiation probe of 10-MeV bremsstrahlung photons to induce fission of the {sup 237}Np sample. The photon source, a 10-MeV electron linear accelerator (linac), is operated in a pulsed mode with a pulse width of {approximately}6 {micro}s at a frequency of {approximately}50 Hz. For all the measurements, 45,000 pulses from the linac were used. The linac output was {approximately}150 R/min at 1 m from the bremsstrahlung source. Neutrons are detected by a medium-efficiency, {sup 3}He-based, neutron detector system between pulses of the interrogating probe. The data acquisition system is gated off during the linac beam burst and for an additional 2000 {micro}s. The neutron detection times are recorded and subsequently analyzed with the Feynman reduced-variance method. This analysis provides a measure of the number of single (N1/s) and double (N2/s) neutron events detected from fission events. These fission events are predominantly produced by the delayed neutrons from fission products resulting from interactions with the 10-MeV bremsstrahlung photons during the interrogating probe burst.

  1. Fusion of neutron rich oxygen isotopes in the crust of accreting neutron stars

    E-Print Network [OSTI]

    Horowitz, C J; Berry, D K

    2007-01-01T23:59:59.000Z

    Fusion reactions in the crust of an accreting neutron star are an important source of heat, and the depth at which these reactions occur is important for determining the temperature profile of the star. Fusion reactions depend strongly on the nuclear charge $Z$. Nuclei with $Z\\le 6$ can fuse at low densities in a liquid ocean. However, nuclei with $Z=8$ or 10 may not burn until higher densities where the crust is solid and electron capture has made the nuclei neutron rich. We calculate the $S$ factor for fusion reactions of neutron rich nuclei including $^{24}$O + $^{24}$O and $^{28}$Ne + $^{28}$Ne. We use a simple barrier penetration model. The $S$ factor could be further enhanced by dynamical effects involving the neutron rich skin. This possible enhancement in $S$ should be studied in the laboratory with neutron rich radioactive beams. We model the structure of the crust with molecular dynamics simulations. We find that the crust of accreting neutron stars may contain micro-crystals or regions of phase sep...

  2. Fusion of neutron rich oxygen isotopes in the crust of accreting neutron stars

    E-Print Network [OSTI]

    C. J. Horowitz; H. Dussan; D. K. Berry

    2008-04-07T23:59:59.000Z

    Fusion reactions in the crust of an accreting neutron star are an important source of heat, and the depth at which these reactions occur is important for determining the temperature profile of the star. Fusion reactions depend strongly on the nuclear charge $Z$. Nuclei with $Z\\le 6$ can fuse at low densities in a liquid ocean. However, nuclei with Z=8 or 10 may not burn until higher densities where the crust is solid and electron capture has made the nuclei neutron rich. We calculate the $S$ factor for fusion reactions of neutron rich nuclei including $^{24}$O + $^{24}$O and $^{28}$Ne + $^{28}$Ne. We use a simple barrier penetration model. The $S$ factor could be further enhanced by dynamical effects involving the neutron rich skin. This possible enhancement in $S$ should be studied in the laboratory with neutron rich radioactive beams. We model the structure of the crust with molecular dynamics simulations. We find that the crust of accreting neutron stars may contain micro-crystals or regions of phase separation. Nevertheless, the screening factors that we determine for the enhancement of the rate of thermonuclear reactions are insensitive to these features. Finally, we calculate the rate of thermonuclear $^{24}$O + $^{24}$O fusion and find that $^{24}$O should burn at densities near $10^{11}$ g/cm$^3$. The energy released from this and similar reactions may be important for the temperature profile of the star.

  3. Neutron scatter camera

    DOE Patents [OSTI]

    Mascarenhas, Nicholas; Marleau, Peter; Brennan, James S.; Krenz, Kevin D.

    2010-06-22T23:59:59.000Z

    An instrument that will directly image the fast fission neutrons from a special nuclear material source has been described. This instrument can improve the signal to background compared to non imaging neutron detection techniques by a factor given by ratio of the angular resolution window to 4.pi.. In addition to being a neutron imager, this instrument will also be an excellent neutron spectrometer, and will be able to differentiate between different types of neutron sources (e.g. fission, alpha-n, cosmic ray, and D-D or D-T fusion). Moreover, the instrument is able to pinpoint the source location.

  4. High energy neutron dosimeter

    DOE Patents [OSTI]

    Sun, Rai Ko S.F. (Albany, CA)

    1994-01-01T23:59:59.000Z

    A device for measuring dose equivalents in neutron radiation fields. The device includes nested symmetrical hemispheres (forming spheres) of different neutron moderating materials that allow the measurement of dose equivalents from 0.025 eV to past 1 GeV. The layers of moderating material surround a spherical neutron counter. The neutron counter is connected by an electrical cable to an electrical sensing means which interprets the signal from the neutron counter in the center of the moderating spheres. The spherical shape of the device allows for accurate measurement of dose equivalents regardless of its positioning.

  5. Semiconductor neutron detector

    DOE Patents [OSTI]

    Ianakiev, Kiril D. (Los Alamos, NM); Littlewood, Peter B. (Cambridge, GB); Blagoev, Krastan B. (Arlington, VA); Swinhoe, Martyn T. (Los Alamos, NM); Smith, James L. (Los Alamos, NM); Sullivan, Clair J. (Los Alamos, NM); Alexandrov, Boian S. (Los Alamos, NM); Lashley, Jason Charles (Santa Fe, NM)

    2011-03-08T23:59:59.000Z

    A neutron detector has a compound of lithium in a single crystal form as a neutron sensor element. The lithium compound, containing improved charge transport properties, is either lithium niobate or lithium tantalate. The sensor element is in direct contact with a monitor that detects an electric current. A signal proportional to the electric current is produced and is calibrated to indicate the neutrons sensed. The neutron detector is particularly useful for detecting neutrons in a radiation environment. Such radiation environment may, e.g. include gamma radiation and noise.

  6. High energy neutron dosimeter

    DOE Patents [OSTI]

    Rai, K.S.F.

    1994-01-11T23:59:59.000Z

    A device for measuring dose equivalents in neutron radiation fields is described. The device includes nested symmetrical hemispheres (forming spheres) of different neutron moderating materials that allow the measurement of dose equivalents from 0.025 eV to past 1 GeV. The layers of moderating material surround a spherical neutron counter. The neutron counter is connected by an electrical cable to an electrical sensing means which interprets the signal from the neutron counter in the center of the moderating spheres. The spherical shape of the device allows for accurate measurement of dose equivalents regardless of its positioning. 2 figures.

  7. The Neutron Imaging System Fielded at the National Ignition Facility

    SciTech Connect (OSTI)

    Merrill, F E; Buckles, R; Clark, D D; Danly, C R; Drury, O B; Dzenitis, J M; Fatherley, V E; Fittinghoff, D N; Gallegos, R; Grim, G P; Guler, N; Loomis, E N; Lutz, S; Malone, R M; Martinson, D D; Mares, D; Morley, D J; Morgan, G L; Oertel, J A; Tregillis, I L; Volegov, P L; Weiss, P B; Wilde, C H

    2012-08-01T23:59:59.000Z

    A neutron imaging diagnostic has recently been commissioned at the National Ignition Facility (NIF). This new system is an important diagnostic tool for inertial fusion studies at the NIF for measuring the size and shape of the burning DT plasma during the ignition stage of Inertial Confinement Fusion (ICF) implosions. The imaging technique utilizes a pinhole neutron aperture, placed between the neutron source and a neutron detector. The detection system measures the two dimensional distribution of neutrons passing through the pinhole. This diagnostic has been designed to collect two images at two times. The long flight path for this diagnostic, 28 m, results in a chromatic separation of the neutrons, allowing the independently timed images to measure the source distribution for two neutron energies. Typically the first image measures the distribution of the 14 MeV neutrons and the second image of the 6-12 MeV neutrons. The combination of these two images has provided data on the size and shape of the burning plasma within the compressed capsule, as well as a measure of the quantity and spatial distribution of the cold fuel surrounding this core.

  8. The Neutron Lifetime

    E-Print Network [OSTI]

    F. E. Wietfeldt

    2014-11-13T23:59:59.000Z

    The decay of the free neutron into a proton, electron, and antineutrino is the prototype semileptonic weak decay and the simplest example of nuclear beta decay. The nucleon vector and axial vector weak coupling constants G_V and G_A determine the neutron lifetime as well as the strengths of weak interaction processes involving free neutrons and protons that are important in astrophysics, cosmology, solar physics and neutrino detection. In combination with a neutron decay angular correlation measurement, the neutron lifetime can be used to determine the first element of the CKM matrix Vud. Unfortunately the two main experimental methods for measuring the neutron lifetime currently disagree by almost 4 sigma. I will present a brief review of the status of the neutron lifetime and prospects for the future.

  9. Carrots for Utilities: Providing Financial Returns for Utility...

    Open Energy Info (EERE)

    Carrots for Utilities: Providing Financial Returns for Utility Investments in Energy Efficiency Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Carrots for Utilities:...

  10. "List of Covered Electric Utilities" under the Public Utility...

    Energy Savers [EERE]

    6 Revised "List of Covered Electric Utilities" under the Public Utility Regulatory Policies Act of 1978 (PURPA) - 2006 Revised Under Title I of the Public Utility Regulatory...

  11. First Neutron Spectrometry Measurement at the HL-2A Tokamak

    E-Print Network [OSTI]

    Xi, Yuan; Xufei, Xie; Zhongjing, Chen; Xingyu, Peng; Tieshuan, Fan; Jinxiang, Chen; Xiangqing, Li; Guoliang, Yuan; Jinwei, Yang; Qingwei, Yang

    2013-01-01T23:59:59.000Z

    A compact neutron spectrometer based on the liquid scintillator is presented for the neutron energy spectrum measurement at the HL-2A tokamak. The spectrometer has been well characterized and a fast digital pulse shape discrimination software has been developed using the charge comparison method. A digitizer data acquisition system with the maximum frequency of 1 MHz can work under the high count rate environment at HL-2A. Specific radiation shielding and magnetic shielding for the spectrometerhas been designed for the neutron spectrum measurement at the HL-2A Tokamak. For the analysis of the pulse height spectrum, dedicated numerical simulation utilizing NUBEAM combining with GENESIS has been made to obtain the neutron energy spectrum, following which the transportation process from the plasma to the detector has been evaluated with Monte Carlo calculations. The distorted neutron energy spectrum has been folded with response matrix of the liquid scintillation spectrometer, and good consistency has been found...

  12. Liquid Argon Cryogenic Detector Calibration by Inelastic Scattering of Neutrons

    E-Print Network [OSTI]

    Sergey Polosatkin; Evgeny Grishnyaev; Alexander Dolgov

    2014-07-10T23:59:59.000Z

    A method for calibration of cryogenic liquid argon detector response to recoils with certain energy -8.2 keV - is proposed. The method utilizes a process of inelastic scattering of monoenergetic neutrons produced by fusion DD neutron generator. Features of kinematics of inelastic scattering cause sufficient (forty times) increase in count rate of useful events relative to traditional scheme exploited elastic scattering with the same recoil energy and compatible energy resolution. The benefits of the proposed scheme of calibration most well implemented with the use of tagged neutron generator as a neutron source that allows to eliminate background originated from casual coincidence of signals on cryogenic detector and additional detector of scattered neutrons.

  13. Beam halo formation from space-charge dominated beams in uniform focusing channels

    SciTech Connect (OSTI)

    O'Connell, J.S. (Booz, Allen and Hamilton, Inc., Arlington, VA (United States)); Wangler, T.P.; Mills, R.S. (Los Alamos National Lab., NM (United States)); Crandall, K.R. (AccSys Technology, Inc., Pleasanton, CA (United States))

    1993-01-01T23:59:59.000Z

    In space-charge dominated beams the nonlinear space-charge forces produce a filamentation pattern, which results in a 2-component beam consisting of an inner core and an outer halo. The halo is very prominent in mismatched beams, and the potential for accelerator activation is of concern for a next generation of cw, high-power proton linacs that could be applied for intense neutron generators to process nuclear materials. We present new results about beam halo and the evolution of space-charge dominated beams from multiparticle simulation of initial laminar beams in a uniform linear focusing channel, and from a model consisting of single particle interactions with a uniform-density beam core. We study the energy gain from particle interactions with the space-charge field of the core, and we identify the resonant characteristic of this interaction as the basic cause of the separation of the beam into the two components. We identify three different particle-trajectory types, and we suggest that one of these types may lead to continuous halo growth, even after the halo is removed by collimators.

  14. Beam halo formation from space-charge dominated beams in uniform focusing channels

    SciTech Connect (OSTI)

    O`Connell, J.S. [Booz, Allen and Hamilton, Inc., Arlington, VA (United States); Wangler, T.P.; Mills, R.S. [Los Alamos National Lab., NM (United States); Crandall, K.R. [AccSys Technology, Inc., Pleasanton, CA (United States)

    1993-06-01T23:59:59.000Z

    In space-charge dominated beams the nonlinear space-charge forces produce a filamentation pattern, which results in a 2-component beam consisting of an inner core and an outer halo. The halo is very prominent in mismatched beams, and the potential for accelerator activation is of concern for a next generation of cw, high-power proton linacs that could be applied for intense neutron generators to process nuclear materials. We present new results about beam halo and the evolution of space-charge dominated beams from multiparticle simulation of initial laminar beams in a uniform linear focusing channel, and from a model consisting of single particle interactions with a uniform-density beam core. We study the energy gain from particle interactions with the space-charge field of the core, and we identify the resonant characteristic of this interaction as the basic cause of the separation of the beam into the two components. We identify three different particle-trajectory types, and we suggest that one of these types may lead to continuous halo growth, even after the halo is removed by collimators.

  15. New source for ultracold neutrons at the Institut Laue-Langevin

    E-Print Network [OSTI]

    Piegsa, F M; Ivanov, S N; Kreuz, M; Leung, K K H; Schmidt-Wellenburg, P; Soldner, T; Zimmer, O

    2014-01-01T23:59:59.000Z

    A new intense superthermal source for ultracold neutrons (UCN) has been installed at a dedicated beam line at the Institut Laue-Langevin. Incident neutrons with a wavelength of 0.89 nm are converted to UCN in a five liter volume filled with superfluid $^4$He at a temperature of about 0.7 K. The UCN can be extracted to room temperature experiments. We present the cryogenic setup of the source, a characterization of the cold neutron beam, and UCN production measurements, where a UCN density in the production volume of at least 55 per cm$^3$ was determined.

  16. New source for ultracold neutrons at the Institut Laue-Langevin

    E-Print Network [OSTI]

    F. M. Piegsa; M. Fertl; S. N. Ivanov; M. Kreuz; K. K. H. Leung; P. Schmidt-Wellenburg; T. Soldner; O. Zimmer

    2014-04-14T23:59:59.000Z

    A new intense superthermal source for ultracold neutrons (UCN) has been installed at a dedicated beam line at the Institut Laue-Langevin. Incident neutrons with a wavelength of 0.89 nm are converted to UCN in a five liter volume filled with superfluid $^4$He at a temperature of about 0.7 K. The UCN can be extracted to room temperature experiments. We present the cryogenic setup of the source, a characterization of the cold neutron beam, and UCN production measurements, where a UCN density in the production volume of at least 55 per cm$^3$ was determined.

  17. Propane cold neutron source: creation and operation experience

    SciTech Connect (OSTI)

    Zemlyanov, M. G.

    1997-09-01T23:59:59.000Z

    In most cold neutron sources, utilized until recently, liquid hydrogen, liquid deuterium and their mixtures were used as a moderating medium. The sources with the liquid hydrogen moderator offer the most specific effectiveness of cold neutron generation. But they are complicated in design, require special safety measures in the course of operation and are very expensive. In this connection, it is of undoubted interest to create a source which, although it yields the specific generation of cold neutrons comparable to the liquid hydrogen one, is safer in operation and simple in design. We assume such a source may be one which uses as a moderator liquid propane cooled to liquid nitrogen temperature.

  18. Three-dimensional boron particle loaded thermal neutron detector

    DOE Patents [OSTI]

    Nikolic, Rebecca J.; Conway, Adam M.; Graff, Robert T.; Kuntz, Joshua D.; Reinhardt, Catherine; Voss, Lars F.; Cheung, Chin Li; Heineck, Daniel

    2014-09-09T23:59:59.000Z

    Three-dimensional boron particle loaded thermal neutron detectors utilize neutron sensitive conversion materials in the form of nano-powders and micro-sized particles, as opposed to thin films, suspensions, paraffin, etc. More specifically, methods to infiltrate, intersperse and embed the neutron nano-powders to form two-dimensional and/or three-dimensional charge sensitive platforms are specified. The use of nano-powders enables conformal contact with the entire charge-collecting structure regardless of its shape or configuration.

  19. Polarized Neutron in Structural Biology Present and Future Outlook

    SciTech Connect (OSTI)

    Zhao, Jinkui [ORNL; Robertson, Lee [ORNL; Herwig, Kenneth W [ORNL; Crabb, Don [University of Virginia

    2013-01-01T23:59:59.000Z

    Hydrogen has a strong polarization-dependent neutron scattering cross section. This property has been exploited in the study of soft matters, especially biological macromolecules. When a polarized neutron beam is scattered off a polarized hydrogenous sample, the otherwise large hydrogen incoherent cross section is drastically reduced while the coherent signal is significantly increased. Past experiments have demonstrated the potentials and benefits of polarized neutron scattering from soft materials. The main technical challenge of polarized neutron scattering from biological matters lies at sample polarization. Dynamic nuclear polarization is a proven yet rather sophisticated technique. Its complexity is one of the main reasons for the technique's slow adoption. The future of polarized neutron scattering in biology may rest largely in neutron protein crystallography. Polarization of protein crystals is much easier to accomplish, since protein crystals are typically rather small (<<1 mm) and only require small and easy- to-operate polarization apparatuses. In addition, the high resolution nature of neutron protein crystallography means that we will be able to study individual atoms using the polarized neutron scattering technique.

  20. Klystron Modulator Design for the Los Alamos Neutron Science Center Accelerator

    SciTech Connect (OSTI)

    Reass, William A. [Los Alamos National Laboratory; Baca, David M. [Los Alamos National Laboratory; Partridge, Edward R. [retired; Rees, Daniel E. [Los Alamos National Laboratory

    2012-06-22T23:59:59.000Z

    This paper will describe the design of the 44 modulator systems that will be installed to upgrade the Los Alamos Neutron Science Center (LANSCE) accelerator RF system. The klystrons can operate up to 86 kV with a nominal 32 Amp beam current with a 120 Hz repetition rate and 15% duty cycle. The klystrons are a mod-anode design. The modulator is designed with analog feedback control to ensure the klystron beam current is flat-top regulated. To achieve fast switching while maintaining linear feedback control, a grid-clamp, totem-pole modulator configuration is used with an 'on' deck and an 'off' deck. The on and off deck modulators are of identical design and utilize a cascode connected planar triode, cathode driven with a high speed MOSFET. The derived feedback is connected to the planar triode grid to enable the flat-top control. Although modern design approaches suggest solid state designs may be considered, the planar triode (Eimac Y-847B) is very cost effective, is easy to integrate with the existing hardware, and provides a simplified linear feedback control mechanism. The design is very compact and fault tolerant. This paper will review the complete electrical design, operational performance, and system characterization as applied to the LANSCE installation.

  1. Fast Beam-Based BPM Calibration

    SciTech Connect (OSTI)

    Bertsche, K.; Loos, H.; Nuhn, H.-D.; Peters, F.; /SLAC

    2012-10-15T23:59:59.000Z

    The Alignment Diagnostic System (ADS) of the LCLS undulator system indicates that the 33 undulator quadrupoles have extremely high position stability over many weeks. However, beam trajectory straightness and lasing efficiency degrade more quickly than this. A lengthy Beam Based Alignment (BBA) procedure must be executed every two to four weeks to re-optimize the X-ray beam parameters. The undulator system includes RF cavity Beam Position Monitors (RFBPMs), several of which are utilized by an automatic feedback system to align the incoming electron-beam trajectory to the undulator axis. The beam trajectory straightness degradation has been traced to electronic drifts of the gain and offset of the BPMs used in the beam feedback system. To quickly recover the trajectory straightness, we have developed a fast beam-based procedure to recalibrate the BPMs. This procedure takes advantage of the high-precision monitoring capability of the ADS, which allows highly repeatable positioning of undulator quadrupoles. This report describes the ADS, the position stability of the LCLS undulator quadrupoles, and some results of the new recovery procedure.

  2. Elimination of influence of neutron-skin size difference of initial colliding nuclei in Pb+Pb collisions

    E-Print Network [OSTI]

    Gao-Feng Wei

    2015-01-22T23:59:59.000Z

    Within an isospin- and momentum-dependent transport model using as an input nucleon density profiles from Hartree-Fock calculations based on a modified Skyrme-like (MSL) model, we study how to eliminate the influence of neutron-skin size difference of initial colliding nuclei in probing the nuclear symmetry energy. Within the current experimental uncertainty range of neutron-skin size of $^{208}$Pb, the Pb+Pb collisions are performed in semicentral and peripheral collisions with impact parameters of 5 and 9fm and at beam energies from 50 MeV/nucleon to 1000 MeV/nucleon, respectively. It is shown that combination of neutron and proton collective flows, i.e., neutron-proton differential elliptic flow, neutron-proton elliptic flow difference, neutron-proton differential transverse flow and neutron-proton transverse flow difference, can effectively eliminate the effects of neutron-skin size difference and thus can be as useful sensitive observables in probing nuclear matter symmetry energy in heavy-ion collisions. Moreover, the combined neutron-proton stopping power including the neutron-proton differential stopping power and neutron-proton stopping power difference can also eliminate the effects of neutron-skin size difference and shows some sensitivities to symmetry energy especially at the lower beam energy.

  3. Neutron resonance spin flippers: Static coils manufactured by electrical discharge machining

    SciTech Connect (OSTI)

    Martin, N.; Kredler, L.; Häußler, W. [Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, 85748 Garching (Germany); Physik-Department E21, Technische Universität München, 85748 Garching (Germany); Wagner, J. N. [Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Dogu, M.; Fuchs, C. [Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, 85748 Garching (Germany); Böni, P. [Physik-Department E21, Technische Universität München, 85748 Garching (Germany)

    2014-07-15T23:59:59.000Z

    Radiofrequency spin flippers (RFSF) are key elements of Neutron Resonance Spin Echo (NRSE) spectrometers, which allow performing controlled manipulations of the beam polarization. We report on the design and test of a new type of RFSF which originality lies in the new manufacturing technique for the static coil. The largely automated procedure ensures reproducible construction as well as an excellent homogeneity of the neutron magnetic resonance condition over the coil volume. Two salient features of this concept are the large neutron window and the closure of the coil by a ?-metal yoke which prevents field leakage outside of the coil volume. These properties are essential for working with large beams and enable new applications with coils tilted with respect to the beam axis such as neutron Larmor diffraction or the study of dispersive excitations by inelastic NRSE.

  4. Electric Utility Industry Update

    Broader source: Energy.gov [DOE]

    Presentation—given at the April 2012 Federal Utility Partnership Working Group (FUPWG) meeting—covers significant electric industry trends and industry priorities with federal customers.

  5. Utility Data Collection Service

    Broader source: Energy.gov [DOE]

    Presentation covers the utility data collection service and is given at the FUPWG 2006 Spring meeting, held on May 3-4, 2006 in Atlanta, Georgia.

  6. Joint Electrical Utilities (Iowa)

    Broader source: Energy.gov [DOE]

    Cities may establish utilities to acquire existing electric generating facilities or distribution systems. Acquisition, in this statute, is defined as city involvement, and includes purchase, lease...

  7. Utility Regulation (Indiana)

    Broader source: Energy.gov [DOE]

    The Indiana Utility Regulatory Commission enforces regulations in this legislation that apply to all individuals, corporations, companies, and partnerships that may own, operate, manage, or control...

  8. Utility Service Renovations

    Broader source: Energy.gov [DOE]

    Any upgrade to utility service provides an opportunity to revisit a Federal building's electrical loads and costs, but it also may provide an economic way to bundle the upgrade with an onsite renewable electricity project during renovation. Upgrading utility service to the site may involve improving or adding a transformer, upgrading utility meters, or otherwise modifying the interconnection equipment or services with the utility. In some cases, the upgrade may change the tariff structure for the facility and may qualify the property for a different structure with lower overall costs. In all cases, the implementation of renewable energy technologies should be identified during the design phase.

  9. Municipal Utility Districts (Texas)

    Broader source: Energy.gov [DOE]

    Municipal Utility Districts, regulated by the Texas Commission on Environmental Quality, may be created for the following purposes: (1) the control, storage, preservation, and distribution of its...

  10. Neutral beam dump with cathodic arc titanium gettering

    SciTech Connect (OSTI)

    Smirnov, A.; Korepanov, S. A.; Putvinski, S. [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States); Krivenko, A. S.; Murakhtin, S. V.; Savkin, V. Ya. [Budker Institute of Nuclear Physics, Novosibirsk 630090 (Russian Federation)

    2011-03-15T23:59:59.000Z

    An incomplete neutral beam capture can degrade the plasma performance in neutral beam driven plasma machines. The beam dumps mitigating the shine-through beam recycling must entrap and retain large particle loads while maintaining the beam-exposed surfaces clean of the residual impurities. The cathodic arc gettering, which provides high evaporation rate coupled with a fast time response, is a powerful and versatile technique for depositing clean getter films in vacuum. A compact neutral beam dump utilizing the titanium arc gettering was developed for a field-reversed configuration plasma sustained by 1 MW, 20-40 keV neutral hydrogen beams. The titanium evaporator features a new improved design. The beam dump is capable of handling large pulsed gas loads, has a high sorption capacity, and is robust and reliable. With the beam particle flux density of 5 x 10{sup 17} H/(cm{sup 2}s) sustained for 3-10 ms, the beam recycling coefficient, defined as twice the ratio of the hydrogen molecular flux leaving the beam dump to the incident flux of high-energy neutral atoms, is {approx}0.7. The use of the beam dump allows us to significantly reduce the recycling of the shine-through neutral beam as well as to improve the vacuum conditions in the machine.

  11. X-ray spectroscopy of neutron star low-mass X-ray binaries

    E-Print Network [OSTI]

    Krauss, Miriam Ilana

    2007-01-01T23:59:59.000Z

    In this thesis, I present work spanning a variety of topics relating to neutron star lowmass X-ray binaries (LMXBs) and utilize spectral information from X-ray observations to further our understanding of these sources. ...

  12. Radiobiological evaluation of new boron delivery agents for boron neutron capture therapy

    E-Print Network [OSTI]

    Chung, Yoonsun

    2008-01-01T23:59:59.000Z

    This thesis evaluates the radiobiological effectiveness of three new boron compounds namely a boronated porphyrin (BOPP) and two liposome formulations for neutron capture therapy (BNCT). The methodology utilizes in vitro ...

  13. Computational methods for efficient nuclear data management in Monte Carlo neutron transport simulations

    E-Print Network [OSTI]

    Walsh, Jonathan A. (Jonathan Alan)

    2014-01-01T23:59:59.000Z

    This thesis presents the development and analysis of computational methods for efficiently accessing and utilizing nuclear data in Monte Carlo neutron transport code simulations. Using the OpenMC code, profiling studies ...

  14. Parallel Computational Modelling of Inelastic Neutron Scattering in Multi-node and Multi-core Architectures 

    E-Print Network [OSTI]

    Garba, M.T.; Gonzales-Velez, H.; Roach, D.L.

    2010-11-26T23:59:59.000Z

    This paper examines the initial parallel implementation of SCATTER, a computationally intensive inelastic neutron scattering routine with polycrystalline averaging capability, for the General Utility Lattice Program (GULP). Of particular importance...

  15. Electron beam magnetic switch for a plurality of free electron lasers

    DOE Patents [OSTI]

    Schlitt, Leland G. (Livermore, CA)

    1984-01-01T23:59:59.000Z

    Apparatus for forming and utilizing a sequence of electron beam segments, each of the same temporal length (substantially 15 nsec), with consecutive beams being separated by a constant time interval of the order of 3 nsec. The beam sequence is used for simultaneous inputs to a plurality of wiggler magnet systems that also accept the laser beams to be amplified by interaction with the co-propagating electron beams. The electron beams are arranged substantially in a circle to allow proper distribution of and simultaneous switching out of the beam segments to their respective wiggler magnets.

  16. Neutron-Proton Analyzing Power Measurements from 375 to 775 Mev

    E-Print Network [OSTI]

    Newsom, C. R.; Hollas, C. L.; Ransome, R. D.; Riley, P. J.; Bonner, BE; Boissevain, J. G. J.; Jarmer, J. J.; McNaughton, M. W.; Simmons, J. E.; Bhatia, T. S.; Glass, G.; Hiebert, John C.; Northcliffe, L. C.; Tippens, W. B.

    1989-01-01T23:59:59.000Z

    proton beam) was of nominal energy, 800 MeV, and intensity 1 ?4 pA. It was tightly bunched by the 201.25 MHz acceleration voltage into very short micro- pulses (0.25 ns width) separated by -5 ns. The neutron beam was produced by passage of the protons...-crossing angle. Various charge-symmetry- breaking models predict a difference in this angle for a polarized proton target as opposed to a polarized neutron beam. The observed energy dependence of this zero- crossing angle and some PSA predictions...

  17. Kinetic simulation of thermonuclear-neutron production by a 10{sup 7}-A deuterium Z pinch

    SciTech Connect (OSTI)

    Welch, D. R.; Rose, D. V.; Thoma, C.; Clark, R. E.; Mostrom, C. B. [Voss Scientific, LLC, Albuquerque, New Mexico 87108 (United States); Stygar, W. A.; Leeper, R. J. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)

    2010-07-15T23:59:59.000Z

    Fully kinetic simulations have demonstrated that at sufficiently high currents, half of the neutrons produced by a deuterium Z-pinch are thermonuclear in origin. At 150-kA pinch current, O. A. Anderson et al. [Phys. Rev. 110, 1375 (1958)] clearly shows that essentially all of the neutrons produced by a deuterium pinch are not thermonuclear, but are initiated by an instability that creates beam-target neutrons. Since this paper, many subsequent authors have supported this result while others have claimed that pinch neutrons are, on the contrary, thermonuclear. To resolve this issue, fully kinetic, collisional, and electromagnetic simulations of the complete time evolution of a deuterium pinch have been performed. The simulations were performed with the implicit particle-in-cell code LSP, as described in D. R. Welch et al. [Phys. Rev. Lett. 103, 255002 (2009)]. At 10{sup 6} -A pinch currents, most of the neutrons are, indeed, beam-target in origin. At 15-MA current, half of the neutrons are thermonuclear and half are beam-target driven by instabilities that produce a power law fall off in the ion energy distribution function at large energy. Simulation results suggest that from 7- to 15-MA current, the fraction of thermonuclear neutrons is not sensitive to current and that the strong dependence of neutron yield on current will continue at currents greater than 15 MA.

  18. Neutron sources and applications

    SciTech Connect (OSTI)

    Price, D.L. [ed.] [Argonne National Lab., IL (United States); Rush, J.J. [ed.] [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1994-01-01T23:59:59.000Z

    Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.

  19. Measurement of delayed neutron yields from {sup 235}U and {sup 238}U

    SciTech Connect (OSTI)

    Kellett, M.A.; Weaver, D.R. [Univ. of Birmingham (United Kingdom); Filip, A. [CEN Cadarache, St. Paul-les-Durance (France)

    1994-12-31T23:59:59.000Z

    Work is in progress at the University of Birmingham, UK, on the preliminary calibration of detectors and neutron beam characterisation required in order to carry out the accurate measurement of the total and absolute delayed neutron yields from the fast fission of uranium 235 and 238. The work is being undertaken in order to try and resolve the discrepancies that exist in the yield for the uranium 238 isotope. The University`s 3 MV Dynamitron accelerator is being used to produce the required neutron fluxes of 10{sup 9} neutrons per steradian per second, as generated via the D(d,n){sup 3}He reaction.

  20. Progress in development of neutron energy spectrometer for deuterium plasma operation in KSTAR

    SciTech Connect (OSTI)

    Tomita, H., E-mail: tomita@nagoya-u.jp; Yamashita, F.; Nakayama, Y.; Morishima, K.; Yamamoto, Y.; Sakai, Y.; Hayashi, S.; Kawarabayashi, J.; Iguchi, T. [Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Cheon, M. S. [Diagnostics Technology Team, ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Isobe, M. [The Graduate University for Advanced Studies, 322-6 Oroshi-cho, Toki 509-5292 (Japan); National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Ogawa, K. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan)

    2014-11-15T23:59:59.000Z

    Two types of DD neutron energy spectrometer (NES) are under development for deuterium plasma operation in KSTAR to understand behavior of beam ions in the plasma. One is based on the state-of-the-art nuclear emulsion technique. The other is based on a coincidence detection of a recoiled proton and a scattered neutron caused by an elastic scattering of an incident DD neutron, which is called an associated particle coincidence counting-NES. The prototype NES systems were installed at J-port in KSTAR in 2012. During the 2012 and 2013 experimental campaigns, multiple shots-integrated neutron spectra were preliminarily obtained by the nuclear emulsion-based NES system.

  1. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    clean coal technology, are not extensively utilized in the cast concrete masonry products (bricks both conventional and clean coal technologies. A clean coal ash is defined as the ash derived from SO2Center for By-Products Utilization USE OF CLASS F FLY ASH AND CLEAN-COAL ASH BLENDS FOR CAST

  2. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    combustion by-products #12;3 generated by using both conventional and clean-coal technologies. A clean-coal that obtained from clean-coal technology, are not utilized in cast-concrete masonry products (bricks, blocksCenter for By-Products Utilization RECENT ADVANCES IN RECYCLING CLEAN- COAL ASH By Tarun R. Naik

  3. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Fellow at the UWM-CBU. His research interests include the use of coal fly ash, coal bottom ash, and used in management, disposal, and sale of coal-combustion by-Center for By-Products Utilization USE OF UNDER-UTILIZED COAL- COMBUSTION PRODUCTS IN PERMEABLE

  4. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    of coal fly ash, coal bottom ash, and used foundry sand in concrete, bricks, blocks, and8 paving stones, Wisconsin. She is involved in management,11 disposal, and sale of coal-combustion by-products. She alsoCenter for By-Products Utilization UNDER-UTILIZED COAL-COMBUSTION PRODUCTS IN PERMEABLE ROADWAY

  5. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization USE OF CLASS F FLY ASH AND CLEAN-COAL ASH BLENDS FOR CAST OF CLASS F FLYASHAND CLEAN-COAL ASHBLENDS FOR CAST CONCRETE PRODUCTS Authors: TarunR.Naik, Director, Center,Illinois Clean Coal Institute RudolphN.Kraus, Research Associate, UWM Center forBy-Products Utilization Shiw S

  6. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    -Milwaukee, P.O. Box 784, Milwaukee, WI 53201 d Project Manager, Illinois Clean Coal Institute * Director UWM products containing clean coal ash compared to conventional coal ash. Utilization of clean coal ash is much products that utilize clean coal ash. With increasing federal regulations on power plant emissions, finding

  7. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization CLEAN COAL BY-PRODUCTS UTILIZATION IN ROADWAY, EMBANKMENTS-fueled plants, particularly use of eastern coals, has lead to the use of clean coal and using advanced sulfur dioxide control technologies. Figure 1 shows clean coal technology benefits(2) . In 1977, the concept

  8. Neutron Science Forum | ORNL

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

    environment for discussion, innovation, and dissemination of information within the neutron scattering community as well as engaging closely related disciplines through...

  9. Lujan Neutron Scattering Center

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

    the inadvertent spread of Technetium 99 by employees and contractors at the Lujan Neutron Scattering Center August 27, 2012-The Laboratory is investigating the inadvertent...

  10. Neutronic fuel element fabrication

    DOE Patents [OSTI]

    Korton, George (Cincinnati, OH)

    2004-02-24T23:59:59.000Z

    This disclosure describes a method for metallurgically bonding a complete leak-tight enclosure to a matrix-type fuel element penetrated longitudinally by a multiplicity of coolant channels. Coolant tubes containing solid filler pins are disposed in the coolant channels. A leak-tight metal enclosure is then formed about the entire assembly of fuel matrix, coolant tubes and pins. The completely enclosed and sealed assembly is exposed to a high temperature and pressure gas environment to effect a metallurgical bond between all contacting surfaces therein. The ends of the assembly are then machined away to expose the pin ends which are chemically leached from the coolant tubes to leave the coolant tubes with internal coolant passageways. The invention described herein was made in the course of, or under, a contract with the U.S. Atomic Energy Commission. It relates generally to fuel elements for neutronic reactors and more particularly to a method for providing a leak-tight metal enclosure for a high-performance matrix-type fuel element penetrated longitudinally by a multiplicity of coolant tubes. The planned utilization of nuclear energy in high-performance, compact-propulsion and mobile power-generation systems has necessitated the development of fuel elements capable of operating at high power densities. High power densities in turn require fuel elements having high thermal conductivities and good fuel retention capabilities at high temperatures. A metal clad fuel element containing a ceramic phase of fuel intimately mixed with and bonded to a continuous refractory metal matrix has been found to satisfy the above requirements. Metal coolant tubes penetrate the matrix to afford internal cooling to the fuel element while providing positive fuel retention and containment of fission products generated within the fuel matrix. Metal header plates are bonded to the coolant tubes at each end of the fuel element and a metal cladding or can completes the fuel-matrix enclosure by encompassing the sides of the fuel element between the header plates.

  11. Ultracold-neutron infrastructure for the gravitational spectrometer GRANIT

    E-Print Network [OSTI]

    P. Schmidt-Wellenburg; K. H. Andersen; P. Courtois; M. Kreuz; S. Mironov; V. V. Nesvizhevsky; G. Pignol; K. V. Protasov; T. Soldner; F. Vezzu; O. Zimmer

    2009-01-29T23:59:59.000Z

    The gravitational spectrometer GRANIT will be set up at the Institut Laue Langevin. It will profit from the high ultracold neutron density produced by a dedicated source. A monochromator made of crystals from graphite intercalated with potassium will provide a neutron beam with 0.89 nm incident on the source. The source employs superthermal conversion of cold neutrons in superfluid helium, in a vessel made from BeO ceramics with Be windows. A special extraction technique has been tested which feeds the spectrometer only with neutrons with a vertical velocity component v < 20 cm/s, thus keeping the density in the source high. This new source is expected to provide a density of up to 800 1/cm3 for the spectrometer.

  12. Ultracold-neutron infrastructure for the gravitational spectrometer GRANIT

    E-Print Network [OSTI]

    Schmidt-Wellenburg, P; Courtois, P; Kreuz, M; Mironov, S; Nesvizhevsky, V V; Pignol, G; Protasov, K V; Soldner, T; Vezzu, F; Zimmer, O

    2008-01-01T23:59:59.000Z

    The gravitational spectrometer GRANIT will be set up at the Institut Laue Langevin. It will profit from the high ultracold neutron density produced by a dedicated source. A monochromator made of crystals from graphite intercalated with potassium will provide a neutron beam with 8.9 Angstrom incident on the source. The source employs superthermal conversion of cold neutrons in superfluid helium, in a vessel made from BeO ceramics with Be windows. A special extraction technique has been tested which feeds the spectrometer only with neutrons with a vertical velocity component v = 20 cm/s, thus keeping the density in the source high. This new source is expected to provide a density of up to R = 800 cm-3 for the spectrometer.

  13. NEUTRON-ENHANCED CALORIMETRY FOR HADRONS (NECH): FINAL REPORT

    SciTech Connect (OSTI)

    Andrew Stroud, Lee Sawyer

    2012-08-31T23:59:59.000Z

    We present the results of a project to apply scintillator technology recently developed at Louisiana Tech University to hadronic calorimetry. In particular, we developed a prototype calorimeter module incorporating scintillator embedded with metal oxide nanoparticles as the active layers. These metal oxide nanoparticles of gadolinium oxide, have high cross-sections for interactions with slow neutrons. As a part fo this research project, we have developed a novel method for producing plastic scintillators with metal oxide nanoparticles evenly distributed through the plastic without aggregation.We will test the performance of the calorimeter module in test beam and with a neutron source, in order to measure the response to the neutron component of hadronic showers. We will supplement our detector prototyping activities with detailed studies of the effect of neutron component on the resolution of hadronic energy measurements, particular in the next generation of particle flow calorimeters.

  14. Fast neutron transmission spectroscopy for illicit substance detection

    SciTech Connect (OSTI)

    Yule, T.J.; Micklich, B.J.; Fink, C.L.; Sagalovsky, L.

    1996-05-01T23:59:59.000Z

    Fast Neutron Transmission Spectroscopy (FNTS) is being investigated for detecting explosives in luggage and other small containers. It uses an accelerator to generate nanosecond-pulsed neutron beams that strike a target, producing a white source of neutrons. Elemental distributions along projections through the interrogated object are obtained by analyzing neutron transmission data. Tomographic reconstruction is used to determine the spatial variations of individual elemental densities. Elemental densities are combined in a detection algorithm that indicates presence or absence of explosives. The elemental unfolding and tomographic reconstruction algorithms have been validated by application to experimental data. System studies have been performed to study the operational characteristics and limitations of a FNTS system, and to determine the system`s sensitivity to several important parameters such as flight path length and position of the interrogated object.

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

    SciTech Connect (OSTI)

    Reginald M. Ronningen; Igor Remec

    2010-09-11T23:59:59.000Z

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

  16. High Brightness Beam Applications: Energy Recovered Linacs

    SciTech Connect (OSTI)

    Geoffrey A. Krafft

    2005-09-01T23:59:59.000Z

    In the first part of the paper some general statements are made regarding applications suitable for utilizing energy recovered linacs (ERLs) by contrasting their potential performance to that of single pass linacs and storage rings. As a result of their potential for extremely good beam quality in combination with high average beam current, ERLs have been used and considered as drivers of both free electron laser and partially coherent photon sources, from THz through X-rays; as a suitable technology for high energy electron cooling; and as a continuous or semi-continuous electron beam source for high energy colliders. At present, beam requirements tend to be highly matched to end use requirements. By reviewing some of the many examples which have either been reduced to practice, or are being explored presently, one can develop an appreciation for the wide range of parameters being considered in ERL applications.

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

    SciTech Connect (OSTI)

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

    2012-10-15T23:59:59.000Z

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

  18. HFIR History - ORNL Neutron Sciences

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

    has grown to include materials irradiation, neutron activation, and, most recently, neutron scattering. In 2007, HFIR completed the most dramatic transformation in its...

  19. Transmission of Megawatt Relativistic Electron Beams Through Millimeter Apertures

    SciTech Connect (OSTI)

    Arizona State University; Arizona State University; JLAB; MIT; College of William and Mary, JLAB; MIT; JLAB; JLAB; MIT; MIT; Hampton University; MIT; JLAB; MIT; JLAB; MIT; MIT; JLAB; MIT; JLAB; JLAB

    2013-10-01T23:59:59.000Z

    High power, relativistic electron beams from energy recovery linacs have great potential to realize new experimental paradigms for pioneering research in fundamental and applied research. A major design consideration for these new generation of experimental capabilities is the understanding of the halo associated with these bright, intense beams. In this Letter, we report on measurements performed using the 100 MeV, 430 kWatt CW electron beam from the energy recovery linac at the Jeff#11;erson Laboratory's Free Electron Laser facility as it traversed a set of small apertures in a 127 mm long aluminum block. Thermal measurements of the block together with neutron measurements near the beam-target interaction point yielded a consistent understanding of the beam losses. These were determined to be 3 ppm through a 2 mm diameter aperture and were maintained during a 7 hour continuous run.

  20. PARALLEL ION BEAM PROFILE SCAN USING LASER WIRE

    SciTech Connect (OSTI)

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

    2013-01-01T23:59:59.000Z

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

  1. Measurements Of Spin Observables In Pseudoscalar-Meson Photo-Production Using Polarized Neutrons In Solid HD

    SciTech Connect (OSTI)

    Kageya, Tsuneo

    2014-01-01T23:59:59.000Z

    Psuedo-scalar meson photo production measurements have been carried out with longitudinally-polarized neutrons using the circularly and linearly polarized photon beams and the CLAS at Thomas Jefferson National Accelerator Facility (Jlab). The experiment aims to obtain a complete set of spin observables on an efficient neutron target. Preliminary E asymmetries for the exclusive reaction, gamma + n(p)--> pi- + p(p), selecting quasi free neutron kinematics are discussed.

  2. Pocked surface neutron detector

    DOE Patents [OSTI]

    McGregor, Douglas (Whitmore Lake, MI); Klann, Raymond (Bolingbrook, IL)

    2003-04-08T23:59:59.000Z

    The detection efficiency, or sensitivity, of a neutron detector material such as of Si, SiC, amorphous Si, GaAs, or diamond is substantially increased by forming one or more cavities, or holes, in its surface. A neutron reactive material such as of elemental, or any compound of, .sup.10 B, .sup.6 Li, .sup.6 LiF, U, or Gd is deposited on the surface of the detector material so as to be disposed within the cavities therein. The portions of the neutron reactive material extending into the detector material substantially increase the probability of an energetic neutron reaction product in the form of a charged particle being directed into and detected by the neutron detector material.

  3. Public Utilities Act (Illinois)

    Broader source: Energy.gov [DOE]

    This act aims to make energy services in the state reliable and efficient, while preserving the quality if the environment. It states the duties of public utilities in terms of accounts and reports...

  4. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization DRAFT REPORT CARBON DIOXIDE SEQUESTRATION IN CEMENTITIOUS-MILWAUKEE #12;CARBON DIOXIDE SEQUESTRATION IN CEMENTITIOUS PRODUCTS Progress Report by Tarun R. Naik, Rakesh of Carbon Dioxide Sequestration Technologies

  5. Public Utilities (Florida)

    Broader source: Energy.gov [DOE]

    Chapter 366 of the Florida Statutes governs the operation of public utilities, and includes a section pertaining to cogeneration and small power production (366.051). This section establishes the...

  6. Cogeneration - A Utility Perspective

    E-Print Network [OSTI]

    Williams, M.

    1983-01-01T23:59:59.000Z

    Cogeneration has become an extremely popular subject when discussing conservation and energy saving techniques. One of the key factors which effect conservation is the utility viewpoint on PURPA and cogeneration rule making. These topics...

  7. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    subbituminous and lignite coals. It is anticipated that increased number of coal- fired plants will utilize subbituminous and lignite coals to reduce sulfur-related emissions. Some correlation exists between chemical

  8. Gas Utilities (Maine)

    Broader source: Energy.gov [DOE]

    Rules regarding the production, sale, and transfer of manufactured gas will also apply to natural gas. This section regulates natural gas utilities that serve ten or more customers, more than one...

  9. Utility and Industrial Partnerships

    E-Print Network [OSTI]

    Sashihara, T. F.

    In the past decade, many external forces have shocked both utilities and their large industrial customers into seeking more effective ways of coping and surviving. One such way is to develop mutually beneficial partnerships optimizing the use...

  10. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    -Products Utilization E-mail: ymchun@uwm.edu and F. D. Botha Project Manager, Illinois Clean Coal Institute 5776 Coal, University of Wisconsin-Milwaukee, Milwaukee, WI, USA. 4 Project Manager, Illinois Clean Coal Institute

  11. Gas Utilities (New York)

    Broader source: Energy.gov [DOE]

    This chapter regulates natural gas utilities in the State of New York, and describes standards and procedures for gas meters and accessories, gas quality, line and main extensions, transmission and...

  12. Extraction Utility Design Specification

    Energy Savers [EERE]

    Extraction Utility Design Specification January 11, 2011 Document Version 1.9 1 Revision History Date Version Section and Titles Author Summary of Change January 15, 2010 1.0 All...

  13. Utility Metering- AGL Resources

    Broader source: Energy.gov [DOE]

    Presentation—given at the Spring 2013 Federal Utility Partnership Working Group (FUPWG) meeting—discusses AGL Resources metering, including interruptible rate customers, large users, and meeting federal metering goals.

  14. Measurements of ultracold neutron lifetimes in solid deuterium

    E-Print Network [OSTI]

    C. L. Morris; J. M. Anaya; T. J. Bowles; B. W. Filippone; P. Geltenbort; R. E. Hill; M. Hino; S. Hoedl; G. E. Hogan; T. M. Ito; T. Kawai; K. Kirch; S. K. Lamoreaux; C. -Y. Liu; M. Makela; L. J. Marek; J. W. Martin; R. N. Mortensen; A. Pichlmaier; A. Saunders; S. J. Seestrom; D. Smith; W. Teasdale; B. Tipton; M. Utsuro; A. R. Young; J. Yuan

    2001-09-28T23:59:59.000Z

    We present the first measurements of the survival time of ultracold neutrons (UCNs) in solid deuterium SD2. This critical parameter provides a fundamental limitation to the effectiveness of superthermal UCN sources that utilize solid ortho-deuterium as the source material. Superthermal UCN sources offer orders of magnitude improvement in the available densities of UCNs, and are of great importance to fundamental particle-physics experiments such as searches for a static electric dipole moment and lifetime measurements of the free neutron. These measurements are performed utilizing a SD2 source coupled to a spallation source of neutrons, providing a demonstration of UCN production in this geometry and permitting systematic studies of the influence of thermal up-scatter and contamination with para-deuterium on the UCN survival time.

  15. Demonstration of a solid deuterium source of ultra-cold neutrons

    E-Print Network [OSTI]

    A. Saunders; J. M. Anaya; T. J. Bowles; B. W. Filippone; P. Geltenbort; R. E. Hill; M. Hino; S. Hoedl; G. E. Hogan; T. M. Ito; K. W. Jones; T. Kawai; K. Kirch; S. K. Lamoreaux; C. -Y. Liu; M. Makela; L. J. Marek; J. W. Martin; C. L. Morris; R. N. Mortensen; A. Pichlmaier; S. J. Seestrom; A. Serebrov; D. Smith; W. Teasdale; B. Tipton; R. B. Vogelaar; A. R. Young; J. Yuan

    2003-12-18T23:59:59.000Z

    Ultra-cold neutrons (UCN), neutrons with energies low enough to be confined by the Fermi potential in material bottles, are playing an increasing role in measurements of fundamental properties of the neutron. The ability to manipulate UCN with material guides and bottles, magnetic fields, and gravity can lead to experiments with lower systematic errors than have been obtained in experiments with cold neutron beams. The UCN densities provided by existing reactor sources limit these experiments. The promise of much higher densities from solid deuterium sources has led to proposed facilities coupled to both reactor and spallation neutron sources. In this paper we report on the performance of a prototype spallation neutron-driven solid deuterium source. This source produced bottled UCN densities of 145 +/-7 UCN/cm3, about three times greater than the largest bottled UCN densities previously reported. These results indicate that a production UCN source with substantially higher densities should be possible.

  16. Beam position monitor

    DOE Patents [OSTI]

    Alkire, Randy W.; Rosenbaum, Gerold; Evans, Gwyndaf

    2003-07-22T23:59:59.000Z

    An apparatus for determining the position of an x-ray beam relative to a desired beam axis. Where the apparatus is positioned along the beam path so that a thin metal foil target intersects the x-ray beam generating fluorescent radiation. A PIN diode array is positioned so that a portion of the fluorescent radiation is intercepted by the array resulting in an a series of electrical signals from the PIN diodes making up the array. The signals are then analyzed and the position of the x-ray beam is determined relative to the desired beam path.

  17. BNL ACTIVITIES IN ADVANCED NEUTRON SOURCE DEVELOPMENT: PAST AND PRESENT

    SciTech Connect (OSTI)

    HASTINGS,J.B.; LUDEWIG,H.; MONTANEZ,P.; TODOSOW,M.; SMITH,G.C.; LARESE,J.Z.

    1998-06-14T23:59:59.000Z

    Brookhaven National Laboratory has been involved in advanced neutron sources almost from its inception in 1947. These efforts have mainly focused on steady state reactors beginning with the construction of the first research reactor for neutron beams, the Brookhaven Graphite Research Reactor. This was followed by the High Flux Beam Reactor that has served as the design standard for all the subsequent high flux reactors constructed worldwide. In parallel with the reactor developments BNL has focused on the construction and use of high energy proton accelerators. The first machine to operate over 1 GeV in the world was the Cosmotron. The machine that followed this, the AGS, is still operating and is the highest intensity proton machine in the world and has nucleated an international collaboration investigating liquid metal targets for next generation pulsed spallation sources. Early work using the Cosmotron focused on spallation product studies for both light and heavy elements into the several GeV proton energy region. These original studies are still important today. In the sections below the authors discuss the facilities and activities at BNL focused on advanced neutron sources. BNL is involved in the proton source for the Spallation Neutron source, spectrometer development at LANSCE, target studies using the AGS and state-of-the-art neutron detector development.

  18. BNL Activities in Advanced Neutron Source Development: Past and Present

    SciTech Connect (OSTI)

    Hastings, J.B.; Ludewig, H.; Montanez, P.; Todosow, M.; Smith, G.C.; Larese, J.Z.

    1998-06-14T23:59:59.000Z

    Brookhaven National Laboratory has been involved in advanced neutron sources almost from its inception in 1947. These efforts have mainly focused on steady state reactors beginning with the construction of the first research reactor for neutron beams, the Brookhaven Graphite Research Reactor. This was followed by the High Flux Beam Reactor that has served as the design standard for all the subsequent high flux reactors constructed worldwide. In parallel with the reactor developments BNL has focused on the construction and use of high energy proton accelerators. The first machine to operate over 1 GeV in the world was the Cosmotron. The machine that followed this, the AGS, is still operating and is the highest intensity proton machine in the world and has nucleated an international collaboration investigating liquid metal targets for next generation pulsed spallation sources. Early work using the Cosmotron focused on spallation product studies for both light and heavy elements into the several GeV proton energy region. These original studies are still important today. In this report we discuss the facilities and activities at BNL focused on advanced neutron sources. BNL is involved in the proton source for the Spallation Neutron source, spectrometer development at LANSCE, target studies using the AGS and state-of-the-art neutron detector development.

  19. A cryogenic source for neutron radiography using a TRIGA reactor

    SciTech Connect (OSTI)

    Chesworth, R.H.; Whittemore, W.L. [General Atomic Co., San Diego, CA (United States)

    1980-07-01T23:59:59.000Z

    A subthermal neutron radiographic facility has been established and successfully operated at General Atomic Company's TRIGA facility to interrogate materials exhibiting a Bragg edge in scattering cross section for neutrons below thermal energies. The facility makes use of the 1500 kW TRIGA Mark F as a neutron source, coupled to a moderator volume of solid methane maintained in the temperature range of 10 deg. K to 25 deg. K by a helium-cooled cryostat. A beam of subthermal neutrons (0.005 to 0.002 eV) is scattered from the solid methane through a cadmium aperture up an argon-filled stepped aluminum beam tube to an imaging system at the top of the reactor pool. The subthermal neutron radiographic facility has been used to inspect zirconium billets with a nominal diameter of 355 mm and thicknesses of 200 to 250 mm in production quantities. With an imaging system of gadolinium-phosphor screens and NDT-75 film, acceptable radiographs have been produced in times as low as 6 minutes. The requirements of the radiographic system include producing film densities of 1.3 and imaging standards of Hafnium, Tantalum and Tungsten down to 0.5mm in diameter, through the 250 mm billets. (author)

  20. High Flux Isotope Reactor cold neutron source reference design concept

    SciTech Connect (OSTI)

    Selby, D.L.; Lucas, A.T.; Hyman, C.R. [and others

    1998-05-01T23:59:59.000Z

    In February 1995, Oak Ridge National Laboratory`s (ORNL`s) deputy director formed a group to examine the need for upgrades to the High Flux Isotope Reactor (HFIR) system in light of the cancellation of the Advanced neutron Source Project. One of the major findings of this study was that there was an immediate need for the installation of a cold neutron source facility in the HFIR complex. In May 1995, a team was formed to examine the feasibility of retrofitting a liquid hydrogen (LH{sub 2}) cold source facility into an existing HFIR beam tube. The results of this feasibility study indicated that the most practical location for such a cold source was the HB-4 beam tube. This location provides a potential flux environment higher than the Institut Laue-Langevin (ILL) vertical cold source and maximizes the space available for a future cold neutron guide hall expansion. It was determined that this cold neutron beam would be comparable, in cold neutron brightness, to the best facilities in the world, and a decision was made to complete a preconceptual design study with the intention of proceeding with an activity to install a working LH{sub 2} cold source in the HFIR HB-4 beam tube. During the development of the reference design the liquid hydrogen concept was changed to a supercritical hydrogen system for a number of reasons. This report documents the reference supercritical hydrogen design and its performance. The cold source project has been divided into four phases: (1) preconceptual, (2) conceptual design and testing, (3) detailed design and procurement, and (4) installation and operation. This report marks the conclusion of the conceptual design phase and establishes the baseline reference concept.

  1. Study on collimation and shielding of the back-streaming neutrons at the CSNS target

    E-Print Network [OSTI]

    Han-Tao, Jing; Zheng, Yang

    2013-01-01T23:59:59.000Z

    The back-streaming neutrons from the spallation target at CSNS are very intense, and can pose serious damage problems for the devices in the accelerator-target interface region. To tackle the problems, a possible scheme for this region was studied, namely a specially designed optics for the proton beam line produces two beam waists, and two collimators are placed at the two waist positions to maximize the collimation effect of the back-streaming neutrons. Detailed Monte Carlo simulations with the beams in the two different CSNS phases show the effectiveness of the collimation system, and the radiation dose rate decreases largely in the interface section. This can ensure the use of epoxy coils for the last magnets and other devices in the beam transport line with reasonable lifetimes, e.g. thirty years. The design philosophy for such an accelerator-target interface region can also be applicable to other high-power proton beam applications.

  2. Spallation Neutron Source ring vacuum systems

    SciTech Connect (OSTI)

    Mapes, M.; Hseuh, H.C.; Rank, J.; Smart, L.; Todd, R.; Weiss, D. [Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2006-07-15T23:59:59.000Z

    The Spallation Neutron Source ring, which is presently being commissioned at Oak Ridge National Laboratory, is designed to accumulate high-intensity protons. Ultrahigh vacuum of 10{sup -9} torr is required in the accumulator ring to minimize beam-residual gas ionization. To reduce the secondary-electron yield and the associated electron cloud instability, the ring vacuum chambers are coated with titanium nitride (TiN). In order to minimize radiation exposure, quick-disconnect chain clamp flanges are used in some areas where radiation levels are expected to be high. This article describes the design, fabrication, assembly, and vacuum processing of the ring and beam transport vacuum systems, as well as the associated vacuum instrumentation.

  3. High-efficiency neutron detectors and methods of making same

    DOE Patents [OSTI]

    McGregor, Douglas S.; Klann, Raymond

    2007-01-16T23:59:59.000Z

    Neutron detectors, advanced detector process techniques and advanced compound film designs have greatly increased neutron-detection efficiency. One embodiment of the detectors utilizes a semiconductor wafer with a matrix of spaced cavities filled with one or more types of neutron reactive material such as 10B or 6LiF. The cavities are etched into both the front and back surfaces of the device such that the cavities from one side surround the cavities from the other side. The cavities may be etched via holes or etched slots or trenches. In another embodiment, the cavities are different-sized and the smaller cavities extend into the wafer from the lower surfaces of the larger cavities. In a third embodiment, multiple layers of different neutron-responsive material are formed on one or more sides of the wafer. The new devices operate at room temperature, are compact, rugged, and reliable in design.

  4. "List of Covered Electric Utilities" under the Public Utility...

    Office of Environmental Management (EM)

    8 "List of Covered Electric Utilities" under the Public Utility Regulatory Policies Act of 1978 (PURPA) - 2008 Under Title I of the Public Utility Regulatory Policies Act of 1978...

  5. "List of Covered Electric Utilities" under the Public Utility...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    9 "List of Covered Electric Utilities" under the Public Utility Regulatory Policies Act of 1978 (PURPA) - 2009 Under Title I, Sec. 102(c) of the Public Utility Regulatory Policies...

  6. BEAMS3D Neutral Beam Injection Model

    SciTech Connect (OSTI)

    Lazerson, Samuel

    2014-04-14T23:59:59.000Z

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

  7. Gamma discrimination in pillar structured thermal neutron detectors

    SciTech Connect (OSTI)

    Shao, Q; Radev, R P; Conway, A M; Voss, L F; Wang, T F; Nikolic, R J; Deo, N; Cheung, C L

    2012-03-26T23:59:59.000Z

    Solid-state thermal neutron detectors are desired to replace {sup 3}He tube based technology for the detection of special nuclear materials. {sup 3}He tubes have some issues with stability, sensitivity to microphonics and very recently, a shortage of {sup 3}He. There are numerous solid-state approaches being investigated that utilize various architectures and material combinations. By using the combination of high-aspect-ratio silicon PIN pillars, which are 2 {micro}m wide with a 2 {micro}m separation, arranged in a square matrix, and surrounded by {sup 10}B, the neutron converter material, a high efficiency thermal neutron detector is possible. Besides intrinsic neutron detection efficiency, neutron to gamma discrimination is an important figure of merit for unambiguous signal identification. In this work, theoretical calculations and experimental measurements are conducted to determine the effect of structure design of pillar structured thermal neutron detectors including: intrinsic layer thickness, pillar height, substrate doping and incident gamma energy on neutron to gamma discrimination.

  8. Center for Beam Physics

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01T23:59:59.000Z

    interactions, ultra-high intensity lasers, 3D Laser Imagingconcepts, ultra-high intensity lasers, x-ray generation,interests: Ultra-high vacuum, particle beam and laser beam

  9. Hypernuclear Physics for Neutron Stars

    E-Print Network [OSTI]

    Jurgen Schaffner-Bielich

    2008-01-24T23:59:59.000Z

    The role of hypernuclear physics for the physics of neutron stars is delineated. Hypernuclear potentials in dense matter control the hyperon composition of dense neutron star matter. The three-body interactions of nucleons and hyperons determine the stiffness of the neutron star equation of state and thereby the maximum neutron star mass. Two-body hyperon-nucleon and hyperon-hyperon interactions give rise to hyperon pairing which exponentially suppresses cooling of neutron stars via the direct hyperon URCA processes. Non-mesonic weak reactions with hyperons in dense neutron star matter govern the gravitational wave emissions due to the r-mode instability of rotating neutron stars.

  10. Center for Beam Physics

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01T23:59:59.000Z

    FEL Collaboration: Photocathode/SCRF Collaboration: Two-BeamUniversity on Photocathode/ SCRF technology, LBNL-BNL on

  11. Beam Dynamics for ARIA

    E-Print Network [OSTI]

    Ekdahl, Carl

    2015-01-01T23:59:59.000Z

    Beam dynamics issues are assessed for a new linear induction electron accelerator being designed for flash radiography of large explosively driven hydrodynamic experiments. Special attention is paid to equilibrium beam transport, possible emittance growth, and beam stability. It is concluded that a radiographic quality beam will be produced possible if engineering standards and construction details are equivalent to those on the present radiography accelerators at Los Alamos.

  12. Utility View of Risk Assessment

    E-Print Network [OSTI]

    Bickham, J.

    This paper will address a utility perspective in regard to risk assessment, reliability, and impact on the utility system. Discussions will also include the critical issues for utilities when contracting for energy and capacity from cogenerators...

  13. HYSPEC : A CRYSTAL TIME OF FLIGHT HYBRID SPECTROMETER FOR THE SPALLATION NEUTRON SOURCE.

    SciTech Connect (OSTI)

    SHAPIRO,S.M.; ZALIZNYAK,I.A.

    2002-12-30T23:59:59.000Z

    This document lays out a proposal by the Instrument Development Team (IDT) composed of scientists from leading Universities and National Laboratories to design and build a conceptually new high-flux inelastic neutron spectrometer at the pulsed Spallation Neutron Source (SNS) at Oak Ridge. This instrument is intended to supply users of the SNS and scientific community, of which the IDT is an integral part, with a platform for ground-breaking investigations of the low-energy atomic-scale dynamical properties of crystalline solids. It is also planned that the proposed instrument will be equipped with a polarization analysis capability, therefore becoming the first polarized beam inelastic spectrometer in the SNS instrument suite, and the first successful polarized beam inelastic instrument at a pulsed spallation source worldwide. The proposed instrument is designed primarily for inelastic and elastic neutron spectroscopy of single crystals. In fact, the most informative neutron scattering studies of the dynamical properties of solids nearly always require single crystal samples, and they are almost invariably flux-limited. In addition, in measurements with polarization analysis the available flux is reduced through selection of the particular neutron polarization, which puts even more stringent limits on the feasibility of a particular experiment. To date, these investigations have mostly been carried out on crystal spectrometers at high-flux reactors, which usually employ focusing Bragg optics to concentrate the neutron beam on a typically small sample. Construction at Oak Ridge of the high-luminosity spallation neutron source, which will provide intense pulsed neutron beams with time-averaged fluxes equal to those at medium-flux reactors, opens entirely new opportunities for single crystal neutron spectroscopy. Drawing upon experience acquired during decades of studies with both crystal and time-of-flight (TOF) spectrometers, the IDT has developed a conceptual design for a focused-beam, hybrid time-of-flight instrument with a crystal monochromator for the SNS called HYSPEC (an acronym for hybrid spectrometer). The proposed instrument has a potential to collect data more than an order of magnitude faster than existing steady-source spectrometers over a wide range of energy transfer ({h_bar}{omega}) and momentum transfer (Q) space, and will transform the way that data in elastic and inelastic single-crystal spectroscopy are collected. HYSPEC is optimized to provide the highest neutron flux on sample in the thermal and epithermal neutron energy ranges at a good-to-moderate energy resolution. By providing a flux on sample several times higher than other inelastic instruments currently planned for the SNS, the proposed instrument will indeed allow unique ground-breaking measurements, and will ultimately make polarized beam studies at a pulsed spallation source a realistic possibility.

  14. Switchable radioactive neutron source device

    DOE Patents [OSTI]

    Stanford, G.S.; Rhodes, E.A.; Devolpi, A.; Boyar, R.E.

    1987-11-06T23:59:59.000Z

    This invention is a switchable neutron generating apparatus comprised of a pair of plates, the first plate having an alpha emitter section on it and the second plate having a target material portion on it which generates neutrons when its nuclei absorb an alpha particle. In operation, the alpha portion of the first plate is aligned with the neutron portion of the second plate to produce neutrons and brought out of alignment to cease production of neutrons. 3 figs.

  15. Switchable radioactive neutron source device

    DOE Patents [OSTI]

    Boyar, Robert E. (La Grange, IL); DeVolpi, Alexander (Bolingbrook, IL); Stanford, George S. (Downers Grove, IL); Rhodes, Edgar A. (Woodridge, IL)

    1989-01-01T23:59:59.000Z

    This invention is a switchable neutron generating apparatus comprised of a pair of plates, the first plate having an alpha emitter section on it and the second plate having a target material portion on it which generates neutrons when its nuclei absorb an alpha particle. In operation, the alpha portion of the first plate is aligned with the neutron portion of the second plate to produce neutrons and brought out of alignment to cease production of neutrons.

  16. Development of a fast neutron therapy beam placement film technique 

    E-Print Network [OSTI]

    Baron, Robert Layton

    1971-01-01T23:59:59.000Z

    by the fibro sarcoma. . . . . . . . . . . . . . . . . . ~ 31 32 39 40 Figure 10. This roentgenograph of subject OA276 shows the position of the Pb-covered stint used in skin-sparing experiments. 11. The head of Dog FOA276 shows good contrast between... was 9. 8 rads. 45 14. This screened placement film of Candy required only a 0. 88 rad dose on Kodak RP-14 film. 46 15. Dog FOA272 was the subject of this 0. 62 rad dose, CaWO screened placement film on Kodak RP-14 film. . . 47 4 16. This placement...

  17. World record neutron beam at Los Alamos National Laboratory

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensus Initiative 2004MoreWorld

  18. 6.21 Improving Neutron Beams for Cancer Treatment

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032) -Less isNFebruaryOctober 2, AlgeriaQ1 Q2 Q3 U . S . D E 2 3 4801

  19. Utility Power Plant Construction (Indiana)

    Broader source: Energy.gov [DOE]

    This statute requires a certificate of necessity from the Indiana Utility Regulatory Commission for the construction, purchase, or lease of an electricity generation facility by a public utility.

  20. GSA-Utility Interconnection Agreements

    Broader source: Energy.gov [DOE]

    Presentation—given at at the Fall 2012 Federal Utility Partnership Working Group (FUPWG) meeting—covers the General Service Administration's (GSA's) utility interconnection agreements.

  1. BBEE Public Utility Conference Call

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

    BBEE Public Utility Conference Call May 19, 2011 - Summary Summer Goodwin, BPA, welcomed public utility representative participants, asked them to introduce themselves, and...

  2. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    2008-04-22T23:59:59.000Z

    A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

  3. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    2009-12-29T23:59:59.000Z

    A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

  4. Strangeness in Neutron Stars

    E-Print Network [OSTI]

    Fridolin Weber; Alexander Ho; Rodrigo P. Negreiros; Philip Rosenfield

    2006-04-20T23:59:59.000Z

    It is generally agreed on that the tremendous densities reached in the centers of neutron stars provide a high-pressure environment in which several intriguing particles processes may compete with each other. These range from the generation of hyperons to quark deconfinement to the formation of kaon condensates and H-matter. There are theoretical suggestions of even more exotic processes inside neutron stars, such as the formation of absolutely stable strange quark matter. In the latter event, neutron stars would be largely composed of strange quark matter possibly enveloped in a thin nuclear crust. This paper gives a brief overview of these striking physical possibilities with an emphasis on the role played by strangeness in neutron star matter, which constitutes compressed baryonic matter at ultra-high baryon number density but low temperature which is no accessible to relativistic heavy ion collision experiments.

  5. Shifting scintillator neutron detector

    DOE Patents [OSTI]

    Clonts, Lloyd G; Cooper, Ronald G; Crow, Jr., Morris Lowell; Hannah, Bruce W; Hodges, Jason P; Richards, John D; Riedel, Richard A

    2014-03-04T23:59:59.000Z

    Provided are sensors and methods for detecting thermal neutrons. Provided is an apparatus having a scintillator for absorbing a neutron, the scintillator having a back side for discharging a scintillation light of a first wavelength in response to the absorbed neutron, an array of wavelength-shifting fibers proximate to the back side of the scintillator for shifting the scintillation light of the first wavelength to light of a second wavelength, the wavelength-shifting fibers being disposed in a two-dimensional pattern and defining a plurality of scattering plane pixels where the wavelength-shifting fibers overlap, a plurality of photomultiplier tubes, in coded optical communication with the wavelength-shifting fibers, for converting the light of the second wavelength to an electronic signal, and a processor for processing the electronic signal to identify one of the plurality of scattering plane pixels as indicative of a position within the scintillator where the neutron was absorbed.

  6. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2005-06-14T23:59:59.000Z

    A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

  7. The Mission and Technology of a Gas Dynamic Trap Neutron Source for Fusion Material and Component Testing and Qualification

    SciTech Connect (OSTI)

    Molvik, A W; Simonen, T C

    2009-07-17T23:59:59.000Z

    This report summarizes discussions and conclusions of the workshop to 'Assess The Mission and Technology of a Gas Dynamic Trap Neutron Source for Fusion Material and Component Testing and Qualification'. The workshop was held at LBNL, Berkeley, CA on March 12, 2009. Most workshop attendees have worked on magnetic mirror systems, several have worked on similar neutron source designs, and others are knowledgeable of materials, fusion component, and neutral beams The workshop focused on the gas dynamic trap DT Neutron Source (DTNS) concept being developed at the Budker Institute of Nuclear Physics (BINP) in Novosibirsk, Russia. The DTNS may be described as a line source of neutrons, in contrast to a spallation or a D-Lithium source with neutrons beaming from a point, or a tokamak volume source. The DTNS is a neutral beam driven linear plasma system with magnetic mirrors to confine the energetic deuterium and tritium beam injected ions, which produce the 14 MeV neutrons. The hot ions are imbedded in warm-background plasma, which traps the neutral atoms and provides both MHD and micro stability to the plasma. The 14 MeV neutron flux ranges typically at the level of 1 to 4 MW/m2.

  8. Computational Benchmark Calculations Relevant to the Neutronic Design of the Spallation Neutron Source (SNS)

    SciTech Connect (OSTI)

    Gallmeier, F.X.; Glasgow, D.C.; Jerde, E.A.; Johnson, J.O.; Yugo, J.J.

    1999-11-14T23:59:59.000Z

    The Spallation Neutron Source (SNS) will provide an intense source of low-energy neutrons for experimental use. The low-energy neutrons are produced by the interaction of a high-energy (1.0 GeV) proton beam on a mercury (Hg) target and slowed down in liquid hydrogen or light water moderators. Computer codes and computational techniques are being benchmarked against relevant experimental data to validate and verify the tools being used to predict the performance of the SNS. The LAHET Code System (LCS), which includes LAHET, HTAPE ad HMCNP (a modified version of MCNP version 3b), have been applied to the analysis of experiments that were conducted in the Alternating Gradient Synchrotron (AGS) facility at Brookhaven National Laboratory (BNL). In the AGS experiments, foils of various materials were placed around a mercury-filled stainless steel cylinder, which was bombarded with protons at 1.6 GeV. Neutrons created in the mercury target, activated the foils. Activities of the relevant isotopes were accurately measured and compared with calculated predictions. Measurements at BNL were provided in part by collaborating scientists from JAERI as part of the AGS Spallation Target Experiment (ASTE) collaboration. To date, calculations have shown good agreement with measurements.

  9. Utility Community Solar Handbook- Understanding and Supporting Utility Program Development

    Broader source: Energy.gov [DOE]

    The "Utility Community Solar Handbook: Understanding and Supporting Utility Program Development" provides the utility's perspective on community solar program development and is a resource for government officials, regulators, community organizers, solar energy advocates, non-profits, and interested citizens who want to support their local utilities in implementing projects.

  10. Neutrons from multifragmentation reactions

    E-Print Network [OSTI]

    W. Trautmann; A. S. Botvina; J. Brzychczyk; N. Buyukcizmeci; I. N. Mishustin; P. Pawlowski; ALADIN2000 Collaboration

    2011-08-29T23:59:59.000Z

    The neutron emission in the fragmentation of stable and radioactive Sn and La projectiles of 600 MeV per nucleon has been studied with the Large Neutron Detector LAND coupled to the ALADIN forward spectrometer at SIS. A cluster-recognition algorithm is used to identify individual particles within the hit distributions registered with LAND. The obtained momentum distributions are extrapolated over the full phase space occupied by the neutrons from the projectile-spectator source. The mean multiplicities of spectator neutrons reach values of up to 12 and depend strongly on the isotopic composition of the projectile. An effective source temperature of T approx. 3 - 4 MeV is deduced from the transverse momentum distributions. For the interpretation of the data, calculations with the Statistical Multifragmentation Model for a properly chosen ensemble of excited sources were performed. The possible modification of the liquid-drop parameters of the fragment description in the hot environment is studied, and a significant reduction of the symmetry-term coefficient is found necessary to simultaneously reproduce the neutron multiplicities and the mean neutron-to-proton ratios /Z of Z <= 10 fragments. Because of the similarity of the freeze-out conditions with those encountered in supernova scenarios, this is of astrophysical interest.

  11. Future possibilities with Fermilab neutrino beams

    SciTech Connect (OSTI)

    Saoulidou, Niki

    2008-01-01T23:59:59.000Z

    We will start with a brief overview of neutrino oscillation physics with emphasis on the remaining unanswered questions. Next, after mentioning near future reactor and accelerator experiments searching for a non zero {theta}{sub 13}, we will introduce the plans for the next generation of long-baseline accelerator neutrino oscillation experiments. We will focus on experiments utilizing powerful (0.7-2.1 MW) Fermilab neutrino beams, either existing or in the design phase.

  12. The neutron skin in neutron-rich nuclei at Jefferson Lab

    SciTech Connect (OSTI)

    Dalton, Mark M. [University of Virginia (United States)

    2013-11-07T23:59:59.000Z

    The Jefferson Lab program to measure the symmetry energy of neutron-rich nuclear matter, using precision electroweak methods, is progressing well. The initial measurement by the PREX experiment, leading to a 2-sigma determination of the 'neutron skin' in {sup 208}Pb, has been published. Design and preparation for a further, more-precise measurement on {sup 208}Pb is progressing well and there is general acceptance of the great advantage to a further measurement on {sup 48}Ca. The surprising ancillary result that the beam-normal single-spin asymmetry for {sup 208}Pb is consistent with zero is also now in the literature. This paper will discuss the current experimental situation of the program.

  13. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    of Wisconsin-Milwaukee Submitted to the Electric Power Research Institute August 2009 UWM Center for By-Products-Strength Materials) for help in reducing global warming. Concrete mixtures having slump in the range of three to fourCenter for By-Products Utilization CARBON DIOXIDE SEQUESTRATION IN CEMENTITIOUS PRODUCTS By Tarun R

  14. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    evaluation of dredged material from Newark harbor............................ 7 Soil stabilization utilizing environment in a cost effective way while producing necessary chemicals such as lime. Lime is one of the most purchasing fabric filter bag collectors are emission regulations, capital cost and operating cost [1

  15. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Issued to the Illinois Clean Coal Institute For Project 02-1/3.1D-2 Department of Civil Engineering of technology and market development for controlled low-strength material (CLSM) slurry using Illinois coal ashCenter for By-Products Utilization IMPLEMENTATION OF FLOWABLE SLURRY TECHNOLOGY IN ILLINOIS

  16. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    technologies. A clean-coal ash is defined as the ash derived from SOxand NOxcontrol technologies, and FBC that obtained from clean-coal technology, are not utilized in cast-concrete masonry products (bricks, blocks conventional and clean-coal technologies. Fifteen high-sulfur coal ash samples were obtained from eight

  17. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization CARBON DIOXIDE SEQUESTRATION IN NO-FINES CONCRETE By Tarun R;CARBON DIOXIDE SEQUESTRATION IN NO-FINES CONCRETE ABSTRACT By Tarun, R. Naik, Yoon-moon Chun, Rudolph N. Kraus, and Fethullah Canpolat This paper presents a detailed experimental study on the sequestration

  18. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    , compressive strength, concrete testing, fly ash, high-performance concrete, hot weather, permeability, silica Testing of Concrete", Committee 214, "Evaluation of Results of Strength Tests of Concrete", and CommitteeCenter for By-Products Utilization STRENGTH AND DURABILITY OF HIGH- PERFORMANCE CONCRETE SUBJECTED

  19. INTRODUCTION Ukiah Electric Utility

    E-Print Network [OSTI]

    INTRODUCTION Ukiah Electric Utility Renewable Energy Resources Procurement Plan Per Senate Billlx 2 renewable energy resources, including renewable energy credits, as a specified percentage of Ukiah's total,2011 to December 31, 2013, Ukiah shall procure renewable energy resources equivalent to an average of at least

  20. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    ash to solve the concerns associated with its disposal. Wood ash consists of two different types ash and coal fly ash for use in concrete, was used to determine general suitability of wood ashCenter for By-Products Utilization WOOD ASH: A NEW SOURCE OF POZZOLANIC MATERIAL By Tarun R. Naik

  1. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    the concerns associated with its disposal. Wood ash consists of two different types of materials: fly ash for use as construction materials. Therefore, ASTM C 618, developed for volcanic ash and coal fly ashCenter for By-Products Utilization WOOD ASH: A NEW SOURCE OF POZZOLANIC MATERIAL By Tarun R. Naik

  2. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    beneficial uses of wood ash to meet the challenges associated with its disposal. Wood ash consists of two C 618 [13] developed for volcanic ash and coal fly ash for use in concrete, was used to determineCenter for By-Products Utilization RECYCLING OF WOOD ASH IN CEMENT-BASED CONSTRUCTION MATERIALS

  3. Advanced fossil energy utilization

    SciTech Connect (OSTI)

    Shekhawat, D.; Berry, D.; Spivey, J.; Pennline, H.; Granite, E.

    2010-01-01T23:59:59.000Z

    This special issue of Fuel is a selection of papers presented at the symposium ‘Advanced Fossil Energy Utilization’ co-sponsored by the Fuels and Petrochemicals Division and Research and New Technology Committee in the 2009 American Institute of Chemical Engineers (AIChE) Spring National Meeting Tampa, FL, on April 26–30, 2009.

  4. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    -air entrained concrete without fly ash. Detailed results are presented. Keywords: carbon dioxide sequestrationCenter for By-Products Utilization CO2 SEQUESTRATION IN NON-AIR ENTRAINED CONCRETE By Tarun R. Naik SEQUESTRATION IN NON-AIR ENTRAINED CONCRETE ABSTRACT by Tarun, R. Naik, Yoon-moon Chun, Rudolph N. Kraus

  5. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization CO2 SEQUESTRATION IN NON-AIR ENTRAINED CONCRETE By Tarun R. Naik and Applied Science THE UNIVERSITY OF WISCONSIN­MILWAUKEE #12;1 CO2 SEQUESTRATION IN NON-AIR ENTRAINED-moon Chun The objectives of this project were to sequester carbon dioxide (CO2) in concrete and study

  6. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization CO2 SEQUESTRATION IN NO-FINES CONCRETE By Tarun R. Naik, Timir C Science THE UNIVERSITY OF WISCONSIN­MILWAUKEE #12;1 CO2 SEQUESTRATION IN NO-FINES CONCRETE ABSTRACT of this project were to sequester carbon dioxide (CO2) in concrete and study the effects of carbonation

  7. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    wood with supplementary fuels such as coal, oil, natural gas, and coke by pulp and paper mills and wood, knots, chips, etc. with other supplementary fuels such as coal, oil, natural gas, and coke to generateCenter for By-Products Utilization DEVELOPMENT OF CLSM USING COAL ASH AND WOOD ASH, A SOURCE OF NEW

  8. Physical Plant Utility Department

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    of Massachusetts Amherst Electrical Distribution & Outdoor Lighting 3.0 Table of Contents Page 1 UMass Medium buses at the Eastside sub-station. The Eastside sub-station is comprised of two separate buses with a normally open bus tie. Each bus is automatically backed up by separate utility feeds. The Eastside Sub-station

  9. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization PROPERTIES OF CONCRETE CONTAINING SCRAP TIRE RUBBER in a variety of rubber and plastic products, thermal incineration of waste tires for production of electricity rubber in asphalt mixes, (ii) thermal incineration of worn-out tires for the production of electricity

  10. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization APPLICATION OF SCRAP TIRE RUBBER IN ASPHALTIC MATERIALS: STATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2. PRODUCING CRUMB RUBBER MODIFIER (CRM) FROM USED TIRES . . . . . 3 2.1 PRODUCTION OF CRM THE UNIVERSITY OF WISCONSIN - MILWAUKEE #12;APPLICATION OF SCRAP TIRE RUBBER IN ASPHALTIC MATERIALS: STATE

  11. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Presentationand Publicationat the CBIP International Conference onFly Ash Disposal & Utilization,New Delhi, India, January 1998 foundry sand and slag. Most of these by-products are landfilled, primarily due to non-availability of economically attractive use options. Landfilling is not a desirable option because it not only causes huge

  12. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    tires generated during the year 1990 - 1991 were reused, recycled, or recovered [4]. A number of usesCenter for By-Products Utilization CONSTRUCTION MATERIALS INCORPORATING DISCARDED TIRES By Tarun R - MILWAUKEE #12;CONSTRUCTION MATERIALS INCORPORATING DISCARDED TIRES* By Tarun R. Naik Director, Center for By

  13. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization CHARACTERIZATION AND APPLICATION OF CLASSF FLY ASHCOAL AND CLEAN-COAL #12;-1- CHARACTERIZATION AND APPLICATION OF CLASSF FLYASHCOAL AND CLEAN-COAL ASHFOR CEMENT -Milwaukee (UWM) Daniel D.Banerjee, Project Manager,Illinois Clean Coal Institute RudolphN.Kraus, Research

  14. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    CONTAINING CLEAN-COAL ASH AND CLASS F FLY ASH By Tarun R. Naik, Rudolph N. Kraus, Rafat Siddique of HVFA Concrete Containing Clean-Coal Ash and Class F Fly Ash By Tarun R. Naik Director, UWM Center for By-Products Utilization and Francois Botha Project Manager, Illinois Clean Coal Institute Synopsis

  15. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    flue gas. Detailed results are presented. Keywords: carbon dioxide sequestration, carbonation, carbonCenter for By-Products Utilization CO2 SEQUESTRATION IN FOAMED CONTROLLED LOW STRENGTH MATERIALS #12;1 CO2 SEQUESTRATION IN FOAMED CONTROLLED LOW STRENGTH MATERIALS by Tarun R. Naik, Rudolph N. Kraus

  16. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    was produced by Wisconsin Electric's coal-fired power plants. The criteria for selecting these mixtures was to utilize minimal cost materials, such as coal combustion by-products (fly ash, bottom ash, etc coal combustion waste material (fly ash) to the maximum extent possible while minimizing costs (e

  17. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization USE OF COAL-COMBUSTION PRODUCTS IN PERMEABLE PAVEMNET BASE and Published at the Raymundo Rivera International Symposium on Durability of Concrete, Monterrey, N. L., Mexico THE UNIVERSITY OF WISCONSIN­MILWAUKEE #12;Use of Coal-Combustion Products in Permeable Pavement Base1 2 3 4 5 6 7

  18. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    combustion by-products (such as clean-coal ash) from power plants. Maximum recycling of such by- products regulations and increasing use of low-grade coal, the number of coal-fired power plants with flue gasCenter for By-Products Utilization USE OF CLEAN-COAL ASH FOR MANAGING ASR By Zichao Wu and Tarun R

  19. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization HIGH-STRENGTH HVFA CONCRETE CONTAINING CLEAN COAL ASH By Tarun R #12;1 HIGH-STRENGTH HVFA CONCRETE CONTAINING CLEAN COAL ASH By Tarun R. Naik, Shiw S. Singh, and Bruce for manufacture of cement-based products using ashes generated from combustion of high-sulfur coals. A clean coal

  20. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization USE OF CLEAN COAL ASH AS SETTING TIME REGULATOR IN PORTLAND OF WISCONSIN ­ MILWAUKEE #12;2 Use of Clean Coal Ash as Setting Time Regulator in Portland Cement by Zichao Wu as setting time regulator for portland cement production. In this paper a source of clean coal ash (CCA

  1. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    and paper mills in concrete. INTRODUCTION Concrete is a porous solid that is created by combining four basicCenter for By-Products Utilization CURING TEMPERATURE EFFECTS ON HIGH-PERFORMANCE CONCRETE By Tarun For presentation and publication at the symposium entitled "High-Performance Concrete and Concrete for Marine

  2. Utility spot pricing, California

    E-Print Network [OSTI]

    Schweppe, Fred C.

    1982-01-01T23:59:59.000Z

    The objective of the present spot pricing study carried out for SCE and PG&E is to develop the concepts which wculd lead to an experimental design for spot pricing in the two utilities. The report suggests a set of experiments ...

  3. By-Products Utilization

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    . Naik, Rudolph N. Kraus, Shiw S. Singh, Lori- Lynn C. Pennock, and Bruce Ramme Report No. CBU-2001 with numerous projects on the use of by-product materials including utilization of used foundry sand and fly ash;2 INTRODUCTION Wood FA is generated due to combustion of wood for energy production at pulp and paper mills, saw

  4. The intense slow positron beam facility at the PULSTAR reactor and applications in nano-materials study

    SciTech Connect (OSTI)

    Liu, Ming; Moxom, Jeremy; Hawari, Ayman I. [Nuclear Reactor Program, Department of Nuclear Engineering, North Carolina State University, P.O. Box 7909, Raleigh, NC 27695 (United States); Gidley, David W. [Department of Physics, University of Michigan, 450 Church Street, Ann Arbor MI 48109 (United States)

    2013-04-19T23:59:59.000Z

    An intense slow positron beam has been established at the PULSTAR nuclear research reactor of North Carolina State University. The slow positrons are generated by pair production in a tungsten moderator from gammarays produced in the reactor core and by neutron capture reactions in cadmium. The moderated positrons are electrostatically extracted and magnetically guided out of the region near the core. Subsequently, the positrons are used in two spectrometers that are capable of performing positron annihilation lifetime spectroscopy (PALS) and positron Doppler broadening spectroscopy (DBS) to probe the defect and free volume properties of materials. One of the spectrometers (e{sup +}-PALS) utilizes an rf buncher to produce a pulsed beam and has a timing resolution of 277 ps. The second spectrometer (Ps-PALS) uses a secondary electron timing technique and is dedicated to positronium lifetime measurements with an approximately 1 ns timing resolution. PALS measurements have been conducted in the e{sup +}-PALS spectrometer on a series of nano-materials including organic photovoltaic thin films, membranes for filtration, and polymeric fibers. These studies have resulted in understanding some critical issues related to the development of the examined nano-materials.

  5. Neutron Compound Refractive Prisms - DOE SBIR Phase II Final Report

    SciTech Connect (OSTI)

    Dr. Jay Theodore Cremer, Jr

    2011-06-25T23:59:59.000Z

    The results of the research led to a pulsed electromagnetic periodic magnetic field array (PMF), which coupled with a pair of collimation slits, and a mechanical chopper slit, were able to deflect spin-up neutrons to a band of line-fused neutrons a focal plane heights that correspond to the time-varying magnetic field amplitude. The electromagnetic field PMF produced 5.4 pulses per minute in which each pulse was 50 msec in duration with a full width half maximum (FWHM) of 7.5 msec. The calculated 7.7 mm vertical height of the band of focused spin-up neutrons corresponded closely to the measured 7.5 mm height of the center line of the imaged band of neutrons. The band of deflected spin-up neutrons was 5 mm in vertical width and the bottom of the band was 5 mm above the surface of the PMF pole. The limited exposure time of 3 hours and the smaller 0.78 T magnetic field allowed focused and near focused neutrons of 1.8 ���� to 2.6 ���� neutrons, which were in the tails of the McClellan Nuclear Radiation Center Bay 4 Maxwell Boltzmann distribution of neutrons with peak flux at 1.1-1.2 ����. The electromagnetic PMF was expected to produces a 2.0 T peak magnetic field amplitude, which would be operational at a higher duty factor, rather than the as built 7.5 msec FWHM with pulse repetition frequency of 5.4 pulses per minute. The fabricated pulsed electromagnetic PMF with chopper is expected to perform well on a cold, very cold or ultra cold beam line as a spectrometer or monochromator source of spin-up polarized neutron. In fact there may be a possible use of the PMF to do ultra-cold neutron trapping, see paper by A. I. Frank1, V. G. Nosov, Quantum Effects in a One-Dimensional Magnetic Gravitational Trap for Ultracold Neutrons, JETP Letters, Vol. 79, No. 7, 2004, pp. 313�¢����315. The next step is to find a cold or very cold neutron facility, where further testing or use of the pulsed magnetic field PMF can be pursued.

  6. STEP Utility Bill Analysis Report

    Broader source: Energy.gov [DOE]

    STEP Utility Bill Analysis Report, from the Tool Kit Framework: Small Town University Energy Program (STEP).

  7. STEP Utility Data Release Form

    Broader source: Energy.gov [DOE]

    STEP Utility Data Release Form, from the Tool Kit Framework: Small Town University Energy Program (STEP).

  8. High-flux neutron source based on a liquid-lithium target

    SciTech Connect (OSTI)

    Halfon, S. [Soreq NRC, Yavne, 81800 (Israel) and Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Feinberg, G. [Soreq NRC, Yavne, 81800 (Israel) and Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Arenshtam, A.; Berkovits, D.; Kijel, D.; Nagler, A.; Eliyahu, I.; Silverman, I. [Soreq NRC, Yavne, 81800 (Israel)

    2013-04-19T23:59:59.000Z

    A prototype compact Liquid Lithium Target (LiLiT), able to constitute an accelerator-based intense neutron source, was built. The neutron source is intended for nuclear astrophysical research, boron neutron capture therapy (BNCT) in hospitals and material studies for fusion reactors. The LiLiT setup is presently being commissioned at Soreq Nuclear research Center (SNRC). The lithium target will produce neutrons through the {sup 7}Li(p,n){sup 7}Be reaction and it will overcome the major problem of removing the thermal power generated by a high-intensity proton beam, necessary for intense neutron flux for the above applications. The liquid-lithium loop of LiLiT is designed to generate a stable lithium jet at high velocity on a concave supporting wall with free surface toward the incident proton beam (up to 10 kW). During off-line tests, liquid lithium was flown through the loop and generated a stable jet at velocity higher than 5 m/s on the concave supporting wall. The target is now under extensive test program using a high-power electron-gun. Up to 2 kW electron beam was applied on the lithium flow at velocity of 4 m/s without any flow instabilities or excessive evaporation. High-intensity proton beam irradiation will take place at SARAF (Soreq Applied Research Accelerator Facility) superconducting linear accelerator currently in commissioning at SNRC.

  9. LBNL-46223, CBP Note 350 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS IN THE LHC

    E-Print Network [OSTI]

    Furman, Miguel

    LBNL-46223, CBP Note 350 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS IN THE LHC M. A. Furman, W. C. Turner, Center for Beam Physics, LBNL, Berkeley, CA 94720, USA Abstract We present beam-beam simulation of simulations: (a) to as- sess undesirable effects from LBNL's luminosity monitor- ing scheme for the LHC [2

  10. LBNL-45363, CBP Note 333 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS

    E-Print Network [OSTI]

    Furman, Miguel

    LBNL-45363, CBP Note 333 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS Miguel A. Furman, Center for Beam Physics, LBNL, Berkeley, CA 94720 Abstract We present beam-beam simulation results from a strong undesirable effects from LBNL's sweeping lumi- nosity monitoring scheme for the LHC [1], and (b) to assess

  11. Nucleonic analysis of the ETF neutral-beam-injector-duct and vacuum-pumping-duct shields

    SciTech Connect (OSTI)

    Urban, W.T.; Seed, T.J.; Dudziak, D.J.

    1981-05-01T23:59:59.000Z

    A nucleonic analysis of the Engineering Test Facility neutral-beam-injector-duct and vacuum-pumping-duct shields has been made using a hybrid Monte Carlo/discrete-ordinates method. This method used Monte Carlo to determine internal and external boundary surface sources for subsequent discrete-ordinates calculations of the neutron and gamma-ray transport through the shields. Confidence was provided in both the hybrid method and the results obtained through a comparison with three-dimensional Monte Carlo results. Also determined in the analysis were the energy and angular distributions of neutrons and gamma rays entering the neutral-beam-injector duct from the toroidal plasma chamber, as well as exiting the duct into the neutral-beam-injector chamber. In addition, the energy and angular distributions of neutrons entering the vacuum-pumping chamber were determined.

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

    E-Print Network [OSTI]

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

    2014-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

    2014-09-08T23:59:59.000Z

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

  14. Utility Energy Services Contracts: Enabling Documents Overview...

    Energy Savers [EERE]

    Utility Energy Services Contracts: Enabling Documents Overview Utility Energy Services Contracts: Enabling Documents Overview Presentation covers the utility energy service...

  15. Exotic fission properties of highly neutron-rich Uranium isotopes

    E-Print Network [OSTI]

    L. Satpathy; S. K. Patra; R. K. Choudhury

    2007-03-05T23:59:59.000Z

    The series of Uranium isotopes with $N=154 \\sim 172$ around the magic number N=162/164 are identified to be thermally fissile. The thermal neutron fission of a typical representative $^{249}$U of this region amenable to synthesis in the radioactive ion beam facilities is considered here. Semiempirical study of fission barrier height and width shows this nucleus to be infinitely stable against spontaneous fission due to increase in barrier width arising out of excess neutrons. Calculation of probability of fragment mass yields and microscopic study in relativistic mean field theory, show this nucleus to undergo a new mode of thermal fission decay termed {\\it multifragmentation fission} where a number of prompt scission neutrons are simultaneously released along with the two heavy fission fragments.

  16. Fan-beam intensity modulated proton therapy

    SciTech Connect (OSTI)

    Hill, Patrick [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States)] [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Westerly, David [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Mackie, Thomas [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)] [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques.Methods: A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0–255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets.Results: Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage. Overall, the sharp distal falloff of a proton depth-dose distribution was found to provide sufficient control over the dose distribution to meet objectives, even with coarse lateral resolution and channel widths as large as 2 cm. Treatment plans on both phantom and patient data show that dose conformity suffers when treatments are delivered from less than approximately ten angles. Treatment time for a sample prostate delivery is estimated to be on the order of 10 min, and neutron production is estimated to be comparable to that found for existing collimated systems.Conclusions: Fan beam proton therapy is a method of delivering intensity modulated proton therapy which may be employed as an alternative to magnetic scanning systems. A fan beam of protons can be created by a set of quadrupole magnets and modified by a dual-purpose range and intensity modulator. This can be used to deliver inversely planned treatments, with spot intensities optimized to meet user defined dose objectives. Additionally, the ability of a fan beam delivery system to effectively treat multiple beam spots simultaneously may provide advantages as compared to spot scanning deliveries.

  17. SPALLATION NEUTRON SOURCE OPERATIONAL EXPERIENCE AT 1 MW

    SciTech Connect (OSTI)

    Galambos, John D [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    The Spallation Neutron Source (SNS) has been operating at the MW level for about one year. Experience in beam loss control and machine activation at this power level is presented. Also experience with machine protection systems is reviewed, which is critical at this power level. One of the most challenging operational aspects of high power operation has been attaining high availability, which is also discussed

  18. Neutron Structure — New Results with CLAS at Jefferson Lab

    SciTech Connect (OSTI)

    Sebastian Kuhn

    2006-11-01T23:59:59.000Z

    New measurements using the 6 GeV continuous electron beam and the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab have collected information on the form factors and the unpolarized structure functions of the neutron, with minimal uncertainty from nuclear binding effects. One experiment has also tried to measure these binding effects more directly, using the method of ''spectator tagging''. These experiments are forerunners for an extensive program with the energy-upgraded 12 GeV accelerator at Jefferson Lab.

  19. Extrapolation of neutron-rich isotope cross-sections from projectile fragmentation

    E-Print Network [OSTI]

    M. Mocko; M. B. Tsang; Z. Y. Sun; L. Andronenko; M. Andronenko; F. Delaunay; M. Famiano; W. A. Friedman; V. Henzl; D. Henzlova; H. Hui; X. D. Liu; S. Lukyanov; W. G. Lynch; A. M. Rogers; M. S. Wallace

    2007-05-29T23:59:59.000Z

    Using the measured fragmentation cross sections produced from the 48Ca and 64Ni beams at 140 MeV per nucleon on 9Be and 181Ta targets, we find that the cross sections of unmeasured neutron rich nuclei can be extrapolated using a systematic trend involving the average binding energy. The extrapolated cross-sections will be very useful in planning experiments with neutron rich isotopes produced from projectile fragmentation. The proposed method is general and could be applied to other fragmentation systems including those used in other radioactive ion beam facilities.

  20. Imaging techniques utilizing optical fibers and tomography

    SciTech Connect (OSTI)

    Wilke, M.; King, N.S.P.; Gray, N.; Johnson, D.; Esquibel, D.; Nedrow, P.; Ishiwata, S.

    1985-01-01T23:59:59.000Z

    Two-dimensional, time-dependent images generated by neutrons, gamma rays, and x-rays incident on fast scintillators are relayed to streak and video cameras over optical fibers. Three dimensions, two spatial and one temporal, have been reduced to two, one in space and time utilizing sampling methods permitting reconstruction of a time-dependent, two-dimensional image subsequent to data recording. The manner in which the sampling is done optimized the ability to reconstruct the image via a maximization of entropy algorithm. This method uses four linear fiber optic arrays typically 30 meters long and up to 35 elements each. A further refinement of this technique collapses the linear array information into four single fibers by wavelength multiplexing. This permits economical transmission of the data over kilometer distances to the recording equipment.

  1. Source Terms for HFIR Beam Tube Shielding Analyses, and a Complete Shielding Analysis of the HB-3 Tube

    SciTech Connect (OSTI)

    Bucholz, J.A.

    2000-07-01T23:59:59.000Z

    The High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory is in the midst of a massive upgrade program to enhance experimental facilities. The reactor presently has four horizontal experimental beam tubes, all of which will be replaced or redesigned. The HB-2 beam tube will be enlarged to support more guide tubes, while the HB-4 beam tube will soon include a cold neutron source.

  2. DATA ACQUISITION FOR SNS BEAM LOSS MONITOR SYSTEM

    SciTech Connect (OSTI)

    YENG,Y.GASSNER,D.HOFF,L.WITKOVER,R.

    2003-10-13T23:59:59.000Z

    The Spallation Neutron Source (SNS) beam loss monitor system uses VME based electronics to measure the radiation produced by lost beam. Beam loss signals from cylindrical argon-filled ion chambers and neutron detectors will be conditioned in analog front-end (AFE) circuitry. These signals will be digitized and further processed in a dedicated VME crate. Fast beam inhibit and low-level, long-term loss warnings will be generated to provide machine protection. The fast loss data will have a bandwidth of 35kHz. While the low level, long-term loss data will have much higher sensitivity. This is further complicated by the 3 decade range of intensity as the Ring accumulates beam. Therefore a bandwidth of 100kHz and dynamic range larger than 21 bits data acquisition system will be required for this purpose. Based on the evaluation of several commercial ADC modules in preliminary design phase, a 24 bits Sigma-Delta data acquisition VME bus card was chosen as the SNS BLM digitizer. An associated vxworks driver and EPICS device support module also have been developed at BNL. Simulating test results showed this system is fully qualified for both fast loss and low-level, long-term loss application. The first prototype including data acquisition hardware setup and EPICS software (running database and OPI clients) will be used in SNS Drift Tube Linac (DTL) system commissioning.

  3. Transfer reactions using a low-energy {sup 11}Be beam

    SciTech Connect (OSTI)

    Johansen, Jacob [Department of Physics and Astronomy, Aarhus University (Denmark)

    2011-10-28T23:59:59.000Z

    A series of experiments have been performed to investigate neutron rich beryllium isotopes. Scattering as well as one neutron transfer reactions have been studied using a {sup 11}Be beam on deuteron targets. Bound states of {sup 10,11,12}Be have been studied and reaction cross sections have been calculated. The elastic scattering cross section has shown remarkable structure due to the halo structure of {sup 11}Be.

  4. Intercomparison of radiation protection instrumentation in a pulsed neutron field

    E-Print Network [OSTI]

    Caresana, M; Esposito, A; Ferrarini, M; Golnik, N; Hohmann, E; Leuschner, A; Luszik-Bhadra, M; Manessi, G; Mayer, S; Ott, K; Röhrich, J; Silari, M; Trompier, F; Volnhals, M; Wielunski, M

    2014-01-01T23:59:59.000Z

    In the framework of the EURADOS working group 11, an intercomparison of active neutron survey meters was performed in a pulsed neutron field (PNF). The aim of the exercise was to evaluate the performances of various neutron instruments, including commercially available rem-counters, personal dosemeters and instrument prototypes. The measurements took place at the cyclotron of the Helmholtz-Zentrum Berlin für Materialien und Energie GmbH. The cyclotron is routinely used for proton therapy of ocular tumours, but an experimental area is also available. For the therapy the machine accelerates protons to 68 MeV. The interaction of the proton beam with a thick tungsten target produces a neutron field with energy up to about 60 MeV. One interesting feature of the cyclotron is that the beam can be delivered in bursts, with the possibility to modify in a simple and flexible way the burst length and the ion current. Through this possibility one can obtain radiation bursts of variable duration and intensity. All instru...

  5. Average Soil Water Retention Curves Measured by Neutron Radiography

    SciTech Connect (OSTI)

    Cheng, Chu-Lin [ORNL; Perfect, Edmund [University of Tennessee, Knoxville (UTK); Kang, Misun [ORNL; Voisin, Sophie [ORNL; Bilheux, Hassina Z [ORNL; Horita, Juske [Texas Tech University (TTU); Hussey, Dan [NIST Center for Neutron Research (NCRN), Gaithersburg, MD

    2011-01-01T23:59:59.000Z

    Water retention curves are essential for understanding the hydrologic behavior of partially-saturated porous media and modeling flow transport processes within the vadose zone. In this paper we report direct measurements of the main drying and wetting branches of the average water retention function obtained using 2-dimensional neutron radiography. Flint sand columns were saturated with water and then drained under quasi-equilibrium conditions using a hanging water column setup. Digital images (2048 x 2048 pixels) of the transmitted flux of neutrons were acquired at each imposed matric potential (~10-15 matric potential values per experiment) at the NCNR BT-2 neutron imaging beam line. Volumetric water contents were calculated on a pixel by pixel basis using Beer-Lambert s law after taking into account beam hardening and geometric corrections. To remove scattering effects at high water contents the volumetric water contents were normalized (to give relative saturations) by dividing the drying and wetting sequences of images by the images obtained at saturation and satiation, respectively. The resulting pixel values were then averaged and combined with information on the imposed basal matric potentials to give average water retention curves. The average relative saturations obtained by neutron radiography showed an approximate one-to-one relationship with the average values measured volumetrically using the hanging water column setup. There were no significant differences (at p < 0.05) between the parameters of the van Genuchten equation fitted to the average neutron radiography data and those estimated from replicated hanging water column data. Our results indicate that neutron imaging is a very effective tool for quantifying the average water retention curve.

  6. Utility Maximization under Uncertainty

    E-Print Network [OSTI]

    Li, Jian

    2010-01-01T23:59:59.000Z

    Motivated by several search and optimization problems over uncertain datasets, we study the stochastic versions of a broad class of combinatorial problems where either the existences or the weights of the elements in the input dataset are uncertain. The class of problems that we study includes shortest paths, minimum weight spanning trees, and minimum weight matchings over probabilistic graphs; top-k queries over probabilistic datasets; and other combinatorial problems like knapsack. By noticing that the expected value is inadequate in capturing different types of risk-averse or risk-prone behaviors, we consider a more general objective which is to maximize the expected utility of the solution for some given utility function. For weight uncertainty model, we show that we can obtain a polynomial time approximation algorithm with additive error eps for any eps>0, if there is a pseudopolynomial time algorithm for the exact version of the problem. Our result generalizes several prior works on stochastic shortest ...

  7. First Neutron Spectrometry Measurement at the HL-2A Tokamak

    E-Print Network [OSTI]

    Yuan Xi; Zhang Xing; Xie Xufei; Chen Zhongjing; Peng Xingyu; Fan Tieshuan; Chen Jinxiang; Li Xiangqing; Yuan Guoliang; Yang Jinwei; Yang Qingwei

    2013-06-17T23:59:59.000Z

    A compact neutron spectrometer based on the liquid scintillator is presented for neutron energy spectrum measurements at the HL-2A tokamak. The spectrometer was well characterized and a fast digital pulse shape discrimination software was developed using the charge comparison method. A digitizer data acquisition system with a maximum frequency of 1 MHz can work under an environment with a high count rate at HL-2A tokamak. Specific radiation and magnetic shielding for the spectrometer were designed for the neutron spectrum measurement at the HL-2A tokamak. For pulse height spectrum analysis, dedicated numerical simulation utilizing NUBEAM combined with GENESIS was performed to obtain the neutron energy spectrum. Subsequently, the transportation process from the plasma to the detector was evaluated with Monte Carlo calculations. The distorted neutron energy spectrum was folded with the response matrix of the liquid scintillation spectrometer, and good consistency was found between the simulated and measured pulse height spectra. This neutron spectrometer based on a digital acquisition system could be well adopted for the investigation of the auxiliary heating behavior and the fast-ion related phenomenon on different tokamak devices.

  8. Operational status and future plans for Los Alamos Neutron Science Center

    SciTech Connect (OSTI)

    Jones, Kevin W [Los Alamos National Laboratory; Schoenberg, Kurt F [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    The Los Alamos Neutron Science Center (LANSCE) continues to be a signature experimental science facility at Los Alamos National Laboratory (LANL). The 800 MeV linear proton accelerator provides multiplexed beams to five unique target stations to produce medical radioisotopes, ultra-cold neutrons, thermal and high energy neutrons for material and nuclear science, and to conduct proton radiography of dynamic events. Recent operating experience will be reviewed and the role of an enhanced LANSCE facility in LANL's new signature facility initiative, Matter and Radiation in Extremes (MaRIE) will be discussed.

  9. A radial collimator for a time-of-flight neutron spectrometer

    SciTech Connect (OSTI)

    Stone, M. B.; Abernathy, D. L. [Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Niedziela, J. L.; Loguillo, M. J.; Overbay, M. A. [Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-08-15T23:59:59.000Z

    We have engineered and installed a radial collimator for use in the scattered beam of a neutron time-of-flight spectrometer at a spallation neutron source. The radial collimator may be used with both thermal and epithermal neutrons, reducing the detected scattering intensity due to material outside of the sample region substantially. The collimator is located inside of the sample chamber of the instrument, which routinely cycles between atmospheric conditions and cryogenic vacuum. The oscillation and support mechanism of the collimator allow it to be removed from use without breaking vacuum. We describe here the design and characterization of this radial collimator.

  10. Strangeness in Neutron Stars

    E-Print Network [OSTI]

    Fridolin Weber

    2000-08-23T23:59:59.000Z

    It is generally agreed on that the tremendous densities reached in the centers of neutron stars provide a high-pressure environment in which numerous novel particles processes are likely to compete with each other. These processes range from the generation of hyperons to quark deconfinement to the formation of kaon condensates and H-matter. There are theoretical suggestions of even more exotic processes inside neutron stars, such as the formation of absolutely stable strange quark matter, a configuration of matter even more stable than the most stable atomic nucleus, iron. In the latter event, neutron stars would be largely composed of pure quark matter, eventually enveloped in a thin nuclear crust. No matter which physical processes are actually realized inside neutron stars, each one leads to fingerprints, some more pronounced than others though, in the observable stellar quantities. This feature combined with the unprecedented progress in observational astronomy, which allows us to see vistas with remarkable clarity that previously were only imagined, renders neutron stars to nearly ideal probes for a wide range of physical studies, including the role of strangeness in dense matter.

  11. Portable Neutron Sensors for Emergency Response Operations

    SciTech Connect (OSTI)

    Mukhopadhyay, S., Maurer, R., Detweiler, R.

    2012-06-22T23:59:59.000Z

    This slide-show presents neutron measurement work, including design, use and performance of different neutron detection systems.

  12. Design and evaluation of a wide bandwidth logarithmic-ratio beam position monitor processor for the Proton Storage Ring at the Los Alamos Meson Physics Facility

    E-Print Network [OSTI]

    Carter, Hamilton Blalock

    1994-01-01T23:59:59.000Z

    The Proton Storage Ring (PSR) is a facility used for high intensity neutron studies at the Los Alamos Meson Physics Facility(LAWF), located at the Los Alamos National Laboratories, Los Alamos, New Mexico. A wide bandwidth beam position processor...

  13. Preliminary measurements of neutrons from the D-D reaction in the COMPASS tokamak

    SciTech Connect (OSTI)

    Dankowski, J., E-mail: jan.dankowski@ifj.edu.pl; Kurowski, A.; Twarog, D. [The Henryk Niewodnicza?ski Institute of Nuclear Physics Polish Academy of Sciences, Radzikowskiego 152 Str., PL-31-342 Kraków (Poland); Janky, F.; Stockel, J. [Institute of Plasma Physics AS CR, v.v.i. Za Slovankou 1782/3, 182 00 Prague 8 (Czech Republic)

    2014-08-21T23:59:59.000Z

    Recent results of measured fast neutrons created in the D-D reaction on the COMPASS tokamak during ohmic discharges are presented in this paper. Two different type detectors were used during experiment. He-3 detectors and bubble detectors as a support. The measurements are an introduction for neutron diagnostic on tokamak COMPASS and monitoring neutrons during discharges with Neutral Beam Injection (NBI). The He-3 counters and bubble detectors were located in two positions near tokamak vacuum chamber at a distance less than 40 cm to the centre of plasma. The neutrons flux was observed in ohmic discharges. However, analysis of our results does not indicate any clear source of neutrons production during ohmic discharges.

  14. Precision Measurement of the Position-space Wave Functions of Gravitationally Bound Ultracold Neutrons

    E-Print Network [OSTI]

    Kamiya, Y; Komamiya, S

    2015-01-01T23:59:59.000Z

    Gravity is the most familiar force at our natural length scale. However, it is still exotic from the view point of particle physics. The first experimental study of quantum effects under gravity was performed using a cold neutron beam in 1975. Following this, an investigation of gravitationally bound quantum states using ultracold neutrons was started in 2002. This quantum bound system is now well understood, and one can use it as a tunable tool to probe gravity. In this paper, we review a recent measurement of position-space wave functions of such gravitationally bound states, and discuss issues related to this analysis, such as neutron loss models in a thin neutron guide, the formulation of phase space quantum mechanics, and UCN position sensitive detectors. The quantum modulation of neutron bound states measured in this experiment shows good agreement with the prediction from quantum mechanics.

  15. Fusion-neutron-yield, activation measurements at the Z accelerator: Design, analysis, and sensitivity

    SciTech Connect (OSTI)

    Hahn, K. D., E-mail: kdhahn@sandia.gov; Ruiz, C. L.; Fehl, D. L.; Chandler, G. A.; Knapp, P. F.; Smelser, R. M.; Torres, J. A. [Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123 (United States)] [Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123 (United States); Cooper, G. W.; Nelson, A. J. [Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States)] [Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Leeper, R. J. [Los Alamos National Laboratories, Plasma Physics Group, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratories, Plasma Physics Group, Los Alamos, New Mexico 87545 (United States)

    2014-04-15T23:59:59.000Z

    We present a general methodology to determine the diagnostic sensitivity that is directly applicable to neutron-activation diagnostics fielded on a wide variety of neutron-producing experiments, which include inertial-confinement fusion (ICF), dense plasma focus, and ion beam-driven concepts. This approach includes a combination of several effects: (1) non-isotropic neutron emission; (2) the 1/r{sup 2} decrease in neutron fluence in the activation material; (3) the spatially distributed neutron scattering, attenuation, and energy losses due to the fielding environment and activation material itself; and (4) temporally varying neutron emission. As an example, we describe the copper-activation diagnostic used to measure secondary deuterium-tritium fusion-neutron yields on ICF experiments conducted on the pulsed-power Z Accelerator at Sandia National Laboratories. Using this methodology along with results from absolute calibrations and Monte Carlo simulations, we find that for the diagnostic configuration on Z, the diagnostic sensitivity is 0.037% ± 17% counts/neutron per cm{sup 2} and is ? 40% less sensitive than it would be in an ideal geometry due to neutron attenuation, scattering, and energy-loss effects.

  16. Measurements of neutron-induced reactions in inverse kinematics and applications to nuclear astrophysics

    E-Print Network [OSTI]

    René Reifarth; Yuri A. Litvinov; Anne Endres; Kathrin Göbel; Tanja Heftrich; Jan Glorius; Alexander Koloczek; Kerstin Sonnabend; Claudia Travaglio; Mario Weigand

    2015-07-12T23:59:59.000Z

    Neutron capture cross sections of unstable isotopes are important for neutron-induced nucleosynthesis as well as for technological applications. A combination of a radioactive beam facility, an ion storage ring and a high flux reactor would allow a direct measurement of neutron induced reactions over a wide energy range on isotopes with half lives down to minutes. The idea is to measure neutron-induced reactions on radioactive ions in inverse kinematics. This means, the radioactive ions will pass through a neutron target. In order to efficiently use the rare nuclides as well as to enhance the luminosity, the exotic nuclides can be stored in an ion storage ring. The neutron target can be the core of a research reactor, where one of the central fuel elements is replaced by the evacuated beam pipe of the storage ring. Using particle detectors and Schottky spectroscopy, most of the important neutron-induced reactions, such as (n,$\\gamma$), (n,p), (n,$\\alpha$), (n,2n), or (n,f), could be investigated.

  17. Measurements of neutron-induced reactions in inverse kinematics and applications to nuclear astrophysics

    E-Print Network [OSTI]

    Reifarth, René; Endres, Anne; Göbel, Kathrin; Heftrich, Tanja; Glorius, Jan; Koloczek, Alexander; Sonnabend, Kerstin; Travaglio, Claudia; Weigand, Mario

    2015-01-01T23:59:59.000Z

    Neutron capture cross sections of unstable isotopes are important for neutron-induced nucleosynthesis as well as for technological applications. A combination of a radioactive beam facility, an ion storage ring and a high flux reactor would allow a direct measurement of neutron induced reactions over a wide energy range on isotopes with half lives down to minutes. The idea is to measure neutron-induced reactions on radioactive ions in inverse kinematics. This means, the radioactive ions will pass through a neutron target. In order to efficiently use the rare nuclides as well as to enhance the luminosity, the exotic nuclides can be stored in an ion storage ring. The neutron target can be the core of a research reactor, where one of the central fuel elements is replaced by the evacuated beam pipe of the storage ring. Using particle detectors and Schottky spectroscopy, most of the important neutron-induced reactions, such as (n,$\\gamma$), (n,p), (n,$\\alpha$), (n,2n), or (n,f), could be investigated.

  18. Methods of Beam Cooling

    E-Print Network [OSTI]

    Sessler, A. M.

    2008-01-01T23:59:59.000Z

    of Optical Stochastic Cooling", presented at PAC, (1995).1991). Hangst, J. , "Laser Cooling of a Stored Ion Beam - ATheorem and Phase Space Cooling", Proceedings of the

  19. Broad beam ion implanter

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    1996-01-01T23:59:59.000Z

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

  20. Courses on Beam Physics

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

    is an incomplete listing of course available for beam physics. United States Particle Accelerator School The US Particle Accelerator School provides educational programs in the...

  1. Optical parametric osicllators with improved beam quality

    DOE Patents [OSTI]

    Smith, Arlee V.; Alford, William J.

    2003-11-11T23:59:59.000Z

    An optical parametric oscillator (OPO) having an optical pump, which generates a pump beam at a pump frequency greater than a desired signal frequency, a nonlinear optical medium oriented so that a signal wave at the desired signal frequency and a corresponding idler wave are produced when the pump beam (wave) propagates through the nonlinear optical medium, resulting in beam walk off of the signal and idler waves, and an optical cavity which directs the signal wave to repeatedly pass through the nonlinear optical medium, said optical cavity comprising an equivalently even number of non-planar mirrors that produce image rotation on each pass through the nonlinear optical medium. Utilizing beam walk off where the signal wave and said idler wave have nonparallel Poynting vectors in the nonlinear medium and image rotation, a correlation zone of distance equal to approximately .rho.L.sub.crystal is created which, through multiple passes through the nonlinear medium, improves the beam quality of the OPO output.

  2. Spherical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2006-11-21T23:59:59.000Z

    A spherical neutron generator is formed with a small spherical target and a spherical shell RF-driven plasma ion source surrounding the target. A deuterium (or deuterium and tritium) ion plasma is produced by RF excitation in the plasma ion source using an RF antenna. The plasma generation region is a spherical shell between an outer chamber and an inner extraction electrode. A spherical neutron generating target is at the center of the chamber and is biased negatively with respect to the extraction electrode which contains many holes. Ions passing through the holes in the extraction electrode are focused onto the target which produces neutrons by D-D or D-T reactions.

  3. Ultrafast neutron detector

    DOE Patents [OSTI]

    Wang, Ching L. (Livermore, CA)

    1987-01-01T23:59:59.000Z

    The invention comprises a neutron detector (50) of very high temporal resolution that is particularly well suited for measuring the fusion reaction neutrons produced by laser-driven inertial confinement fusion targets. The detector comprises a biased two-conductor traveling-wave transmission line (54, 56, 58, 68) having a uranium cathode (60) and a phosphor anode (62) as respective parts of the two conductors. A charge line and Auston switch assembly (70, 72, 74) launch an electric field pulse along the transmission line. Neutrons striking the uranium cathode at a location where the field pulse is passing, are enabled to strike the phosphor anode and produce light that is recorded on photographic film (64). The transmission line may be variously configured to achieve specific experimental goals.

  4. Personnel electronic neutron dosimeter

    DOE Patents [OSTI]

    Falk, Roger B. (Lafayette, CO); Tyree, William H. (Boulder, CO)

    1984-12-18T23:59:59.000Z

    A personnel electronic dosimeter includes a neutron-proton and neutron-alpha converter for providing an electrical signal having a magnitude proportional to the energy of a detected proton or alpha particle produced from the converter, a pulse generator circuit for generating a pulse having a duration controlled by the weighed effect of the amplitude of the electrical signal, an oscillator enabled by the pulse for generating a train of clock pulses for a time dependent upon the pulse length, a counter for counting the clock pulses, and an indicator for providing a direct reading and aural alarm when the count indicates that the wearer has been exposed to a selected level of neutron dose equivalent.

  5. Personnel electronic neutron dosimeter

    DOE Patents [OSTI]

    Falk, R.B.; Tyree, W.H.

    1982-03-03T23:59:59.000Z

    A personnel electronic dosimeter includes a neutron-proton and neutron-alpha converter for providing an electrical signal having a magnitude proportional to the energy of a detected proton or alpha particle produced from the converter, a pulse generator circuit for generating a pulse having a duration controlled by the weighed effect of the amplitude of the electrical signal, an oscillator enabled by the pulse for generating a train of clock pulses for a time dependent upon the pulse length, a counter for counting the clock pulses, and an indicator for providing a direct reading and aural alarm when the count indicates that the wearer has been exposed to a selected level of neutron dose equivalent.

  6. Note: Characteristic beam parameter for the line electron gun

    SciTech Connect (OSTI)

    Iqbal, M. [Centre for High Energy Physics, University of the Punjab, Lahore 45590 (Pakistan) [Centre for High Energy Physics, University of the Punjab, Lahore 45590 (Pakistan); Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Islam, G. U. [Centre for High Energy Physics, University of the Punjab, Lahore 45590 (Pakistan)] [Centre for High Energy Physics, University of the Punjab, Lahore 45590 (Pakistan); Zhou, Z.; Chi, Y. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)] [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2013-11-15T23:59:59.000Z

    We have optimized the beam parameters of line source electron gun using Stanford Linear Accelerator Centre electron beam trajectory program (EGUN), utilizing electrostatic focusing only. We measured minimum beam diameter as 0.5 mm that corresponds to power density of 68.9 kW/cm{sup 2} at 13.5 mm in the post-anode region which is more than two-fold (33 kW/cm{sup 2}), of the previously reported results. The gun was operated for the validation of the theoretical results and found in good agreement. The gun is now without any magnetic and electrostatic focusing thus much simpler and more powerful.

  7. Neutron Scattering Tutorials | Neutron Science | ORNL

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire Solar541,9337, 2011 at3,Neutron Scattering Tutorials SHARE

  8. Corrosion resistant neutron absorbing coatings

    DOE Patents [OSTI]

    Choi, Jor-Shan; Farmer, Joseph C; Lee, Chuck K; Walker, Jeffrey; Russell, Paige; Kirkwood, Jon; Yang, Nancy; Champagne, Victor

    2013-11-12T23:59:59.000Z

    A method of forming a corrosion resistant neutron absorbing coating comprising the steps of spray or deposition or sputtering or welding processing to form a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material. Also a corrosion resistant neutron absorbing coating comprising a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material.

  9. Corrosion resistant neutron absorbing coatings

    DOE Patents [OSTI]

    Choi, Jor-Shan (El Cerrito, CA); Farmer, Joseph C. (Tracy, CA); Lee, Chuck K. (Hayward, CA); Walker, Jeffrey (Gaithersburg, MD); Russell, Paige (Las Vegas, NV); Kirkwood, Jon (Saint Leonard, MD); Yang, Nancy (Lafayette, CA); Champagne, Victor (Oxford, PA)

    2012-05-29T23:59:59.000Z

    A method of forming a corrosion resistant neutron absorbing coating comprising the steps of spray or deposition or sputtering or welding processing to form a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material. Also a corrosion resistant neutron absorbing coating comprising a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material.

  10. Federal Utility Partnership Working Group- Utility Interconnection Panel

    Broader source: Energy.gov [DOE]

    Presentation—given at at the Fall 2012 Federal Utility Partnership Working Group (FUPWG) meeting—discusses solar/photovoltaic (PV) projects to connect with utility in California and their issues.

  11. Neutron Science and Technology

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire Solar541,9337, 2011 at3,Neutron Scattering3 Neutron Science

  12. Beam Position and Phase Monitor - Wire Mapping System

    SciTech Connect (OSTI)

    Watkins, Heath A [Los Alamos National Laboratory; Shurter, Robert B. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Kutac, Vincent G. [Los Alamos National Laboratory; Martinez, Derwin [Los Alamos National Laboratory

    2012-04-10T23:59:59.000Z

    The Los Alamos Neutron Science Center (LANSCE) deploys many cylindrical beam position and phase monitors (BPPM) throughout the linac to measure the beam central position, phase and bunched-beam current. Each monitor is calibrated and qualified prior to installation to insure it meets LANSCE requirements. The BPPM wire mapping system is used to map the BPPM electrode offset, sensitivity and higher order coefficients. This system uses a three-axis motion table to position the wire antenna structure within the cavity, simulating the beam excitation of a BPPM at a fundamental frequency of 201.25 MHz. RF signal strength is measured and recorded for the four electrodes as the antenna position is updated. An effort is underway to extend the systems service to the LANSCE facility by replacing obsolete electronic hardware and taking advantage of software enhancements. This paper describes the upgraded wire positioning system's new hardware and software capabilities including its revised antenna structure, motion control interface, RF measurement equipment and Labview software upgrades. The main purpose of the wire mapping system at LANSCE is to characterize the amplitude response versus beam central position of BPPMs before they are installed in the beam line. The wire mapping system is able to simulate a beam using a thin wire and measure the signal response as the wire position is varied within the BPPM aperture.

  13. Wire Scanner Beam Profile Measurements for the LANSCE Facility

    SciTech Connect (OSTI)

    Gilpatrick, John D. [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Martinez, Derwin [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

    2012-05-15T23:59:59.000Z

    The Los Alamos Neutron Science Center (LANSCE) is replacing beam profile measurement systems, commonly known as Wire Scanners (WS). Using the principal of secondary electron emission, the WS measurement system moves a wire or fiber across an impinging particle beam, sampling a projected transverse-beam distribution. Because existing WS actuators and electronic components are either no longer manufactured or home-built with antiquated parts, a new WS beam profile measurement is being designed, fabricated, and tested. The goals for these new WS's include using off-the-shelf components while eliminating antiquated components, providing quick operation while allowing for easy maintainability, and tolerating external radioactivation. The WS measurement system consists of beam line actuators, a cable plant, an electronics processor chassis, and software located both in the electronics chassis (National Instruments LabVIEW) and in the Central Control Room (EPICS-based client software). This WS measurement system will measure Hand H{sup +} LANSCE-facility beams and will also measure less common beams. This paper describes these WS measurement systems.

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

    E-Print Network [OSTI]

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

    2000-01-01T23:59:59.000Z

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

  15. NEUTRON AND NON-NEUTRON NUCLEAR DATA FOR RADIATION DOSIMETRY

    SciTech Connect (OSTI)

    HOLDEN,N.E.

    1999-09-10T23:59:59.000Z

    NEUTRON NUCLEAR DATA THAT IS USED IN REACTOR DOSIMETRY INCLUDE THERMAL NEUTRON CROSS SECTIONS AND NEUTRON RESONANCE INTEGRALS, FISSION SPECTRUM AVERAGED CROSS SECTIONS FOR REACTIONS ON A TARGET NUCLEUS. NON-NEUTRON NUCLEAR DATA USED IN REACTOR DOSIMETRY INCLUDE ISOTOPIC COMPOSITIONS OF TARGET NUCLIDES AND RADIOACTIVE HALF-LIVES, GAMMA-RAY ENERGIES AND INTENSITIES OF REACTION PRODUCT NUCLIDES. ALL OF THESE DATA ARE PERIODICALLY EVALUATED AND RECOMMENDED VALUES ARE PROVIDED IN THE HANDBOOK OF CHEMISTRY AND PHYSICS. THE LATEST RECOMMENDED VALUES ARE DISCUSSED AND THEY ARE CONTRASTED WITH SOME EARLIER NUCLEAR DATA, WHICH WAS PROVIDED WITH NEUTRON DETECTOR FOILS.

  16. Design of a backscatter 14-MeV neutron time-of-flight spectrometer for experiments at ITER

    SciTech Connect (OSTI)

    Dzysiuk, N.; Hellesen, C.; Conroy, S.; Ericsson, G.; Hjalmarsson, A.; Skiba, M. [Div. Applied Nuclear Physics, Dept. Physics and Astronomy, Uppsala University, Box 516, Uppsala, 751 20 (Sweden)

    2014-08-21T23:59:59.000Z

    Neutron energy spectrometry diagnostics play an important role in present-day experiments related to fusion energy research. Measurements and thorough analysis of the neutron emission from the fusion plasma give information on a number of basic fusion performance quantities, on the condition of the neutron source and plasma behavior. Here we discuss the backscatter Time-of-Flight (bTOF) spectrometer concept as a possible instrument for performing high resolution measurements of 14 MeV neutrons. The instrument is based on two sets of scintillators, a first scatterer exposed to a collimated neutron beam and a second detector set placed in the backward direction. The scintillators of the first set are enriched in deuterium to achieve neutron backscattering. The energy resolution and efficiency of a bTOF instrument have been determined for various geometrical configurations. A preliminary design of optimal geometry for the two scintillator sets has been obtained by Monte Carlo simulations based on the MCNPX code.

  17. Tribal Utility Feasibility Study

    SciTech Connect (OSTI)

    Engel, R. A.; Zoellick, J. J.

    2007-06-30T23:59:59.000Z

    The Schatz Energy Research Center (SERC) assisted the Yurok Tribe in investigating the feasibility of creating a permanent energy services program for the Tribe. The original purpose of the DOE grant that funded this project was to determine the feasibility of creating a full-blown Yurok Tribal electric utility to buy and sell electric power and own and maintain all electric power infrastructure on the Reservation. The original project consultant found this opportunity to be infeasible for the Tribe. When SERC took over as project consultant, we took a different approach. We explored opportunities for the Tribe to develop its own renewable energy resources for use on the Reservation and/or off-Reservation sales as a means of generating revenue for the Tribe. We also looked at ways the Tribe can provide energy services to its members and how to fund such efforts. We identified opportunities for the development of renewable energy resources and energy services on the Yurok Reservation that fall into five basic categories: • Demand-side management – This refers to efforts to reduce energy use through energy efficiency and conservation measures. • Off-grid, facility and household scale renewable energy systems – These systems can provide electricity to individual homes and Tribal facilities in areas of the Reservation that do not currently have access to the electric utility grid. • Village scale, micro-grid renewable energy systems - These are larger scale systems that can provide electricity to interconnected groups of homes and Tribal facilities in areas of the Reservation that do not have access to the conventional electric grid. This will require the development of miniature electric grids to serve these interconnected facilities. • Medium to large scale renewable energy development for sale to the grid – In areas where viable renewable energy resources exist and there is access to the conventional electric utility grid, these resources can be developed and sold to the wholesale electricity market. • Facility scale, net metered renewable energy systems – These are renewable energy systems that provide power to individual households or facilities that are connected to conventional electric utility grid.

  18. Extraction Utility Design Specification

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T,OfficeEnd of Year 2010Salt |Exelon GenerationExtraction Utility Design

  19. Utilize Available Resources

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize Available Resources Print As soon as you arrive

  20. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, B.E.; Duncan, D.B.

    1994-02-15T23:59:59.000Z

    Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus is described. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 7 figures.

  1. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, B.E.; Duncan, D.B.

    1993-12-28T23:59:59.000Z

    Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 11 figures.

  2. The tokamak as a neutron source

    SciTech Connect (OSTI)

    Hendel, H.W.; Jassby, D.L.

    1989-11-01T23:59:59.000Z

    This paper describes the tokamak in its role as a neutron source, with emphasis on experimental results for D-D neutron production. The sections summarize tokamak operation, sources of fusion and non-fusion neutrons, principal neutron detection methods and their calibration, neutron energy spectra and fluxes outside the tokamak plasma chamber, history of neutron production in tokamaks, neutron emission and fusion power gain from JET and TFTR (the largest present-day tokamaks), and D-T neutron production from burnup of D-D tritons. This paper also discusses the prospects for future tokamak neutron production and potential applications of tokamak neutron sources. 100 refs., 16 figs., 4 tabs.

  3. First Beam to FACET

    SciTech Connect (OSTI)

    Erickson, R.; Clarke, C.; Colocho, W.; Decker, F.-J.; Hogan, M.; Kalsi, S.; Lipkowitz, N.; Nelson, J.; Phinney, N.; Schuh, P.; Sheppard, J.; Smith, H.; Smith, T.; Stanek, M.; Turner, J.; Warren, J.; Weathersby, S.; Wienands, U.; Wittmer, W.; Woodley, M.; Yocky, G.; /SLAC

    2011-12-13T23:59:59.000Z

    The SLAC 3km linear electron accelerator has been reconfigured to provide a beam of electrons to the new Facility for Advanced Accelerator Experimental Tests (FACET) while simultaneously providing an electron beam to the Linac Coherent Light Source (LCLS). On June 23, 2011, the first electron beam was transported through this new facility. Commissioning of FACET is in progress. On June 23, 2011, an electron beam was successfully transported through the new FACET system to a dump in Sector 20 in the linac tunnel. This was achieved while the last third of the linac, operating from the same control room, but with a separate injector system, was providing an electron beam to the Linac Coherent Light Source (LCLS), demonstrating that concurrent operation of the two facilities is practical. With the initial checkout of the new transport line essentially complete, attention is now turning toward compressing the electron bunches longitudinally and focusing them transversely to support a variety of accelerator science experiments.

  4. Utility spot pricing study : Wisconsin

    E-Print Network [OSTI]

    Caramanis, Michael C.

    1982-01-01T23:59:59.000Z

    Spot pricing covers a range of electric utility pricing structures which relate the marginal costs of electric generation to the prices seen by utility customers. At the shortest time frames prices change every five ...

  5. Rapidly pulsed TRIGA reactor: an intense source for neutron scattering experiments

    SciTech Connect (OSTI)

    Whittemore, William L. [General Atomics, San Diego, CA (United States)

    1994-07-01T23:59:59.000Z

    The need for ever increasing intensities of thermal neutron beams for neutron scattering experiments has stimulated the development of intense steady state research reactors such as the 53-MW ILL reactor at Grenoble. The source flux at the reactor end of the beam ports is typically 10{sup 15}n/cm{sup 2}.s for its thermal neutron beams. To achieve still higher source fluxes of neutrons, the family of pulsing IBR was developed. In this type of facility the pulse repetition rate is low ({approx}5/sec) typically but the instantaneous peak fluxes are high, ranging up to 5 x 10{sup 15}n/cm{sup 2}.s at the surface of the moderator. Another type of intense neutron source is that exemplified by the proton synchrotron accelerators with their spallation targets. The first of these has been the IPNS at Argonne National laboratory. This neutron source produces 30 pulses per second with an individual peak thermal neutron intensity of 4 x 10{sup 14}n/cm{sup 2}.s from the moderator. An equivalent, alternative intense neutron source can be based on a rapidly pulsed TRIGA reactor. With a pulsed thermal neutron intensity of more than 10{sup 15}n/cm{sup 2}.s occurring 50 times per second at the source end of beam ports, the rapidly pulsed TRIGA reactor combines some of the best features of the pulsed fast reactors such as IBR-2 and the spallation neutron sources but with the safety of a thermal neutron reactor with a large, prompt, negative temperature coefficient of reactivity. The initial concept of the rapidly pulsed TRIGA reactor was developed and initially reported in 1966. Subsequently, the standard fuel format for U-ZrH{sub x} fuel has been developed to include a small diameter fuel particularly well suited for the rapidly pulsed application. This fuel is LEU, satisfying all the requirements for non proliferation, and has a very long core life time. In the proposed application, the peak fuel temperature does not vary more than 1 deg. C from the average peak fuel temperatures during each pulse. Hence long term metallurgical stability is thus assured. With a core lifetime that can be designed for up to 10,000 MWD, operation at an average power of 10 MW (with peak pulsed powers of {approx}50 MW) with an equilibrium core can be conducted for 1000 full power days. (author)

  6. Neutron Absorbing Alloys

    DOE Patents [OSTI]

    Mizia, Ronald E. (Idaho Falls, ID); Shaber, Eric L. (Idaho Falls, ID); DuPont, John N. (Whitehall, PA); Robino, Charles V. (Albuquerque, NM); Williams, David B. (Bethlehem, PA)

    2004-05-04T23:59:59.000Z

    The present invention is drawn to new classes of advanced neutron absorbing structural materials for use in spent nuclear fuel applications requiring structural strength, weldability, and long term corrosion resistance. Particularly, an austenitic stainless steel alloy containing gadolinium and less than 5% of a ferrite content is disclosed. Additionally, a nickel-based alloy containing gadolinium and greater than 50% nickel is also disclosed.

  7. A comparison of neutron dose measurement techniques at the K500 Superconducting Cyclotron facility

    E-Print Network [OSTI]

    Ford, Michael Scott

    1989-01-01T23:59:59.000Z

    - tivity in accelerator components, and thus contributing to personnel exposure, than are the cascade neutrons, since evaporation particles are considerably more numerous and their energy is more favorable for capture (Patterson and Thomas 1973... generated by the superconducting accelerator (K500). The existing dosimeter system utilized both the Kodak~ Neutron Track Analysis (NTA) film and GARDRAYIII' 8 mm beta, x, and gamma ray film. The proposed system incorporated a TLD albedo dosimeter and a...

  8. Dose-equivalent neutron dosimeter

    DOE Patents [OSTI]

    Griffith, R.V.; Hankins, D.E.; Tomasino, L.; Gomaa, M.A.M.

    1981-01-07T23:59:59.000Z

    A neutron dosimeter is disclosed which provides a single measurement indicating the amount of potential biological damage resulting from the neutron exposure of the wearer, for a wide range of neutron energies. The dosimeter includes a detecting sheet of track etch detecting material such as a carbonate plastic, for detecting higher energy neutrons, and a radiator layer contaning conversion material such as /sup 6/Li and /sup 10/B lying adjacent to the detecting sheet for converting moderate energy neutrons to alpha particles that produce tracks in the adjacent detecting sheet.

  9. Solid state neutron detector array

    DOE Patents [OSTI]

    Seidel, J.G.; Ruddy, F.H.; Brandt, C.D.; Dulloo, A.R.; Lott, R.G.; Sirianni, E.; Wilson, R.O.

    1999-08-17T23:59:59.000Z

    A neutron detector array is capable of measuring a wide range of neutron fluxes. The array includes multiple semiconductor neutron detectors. Each detector has a semiconductor active region that is resistant to radiation damage. In one embodiment, the array preferably has a relatively small size, making it possible to place the array in confined locations. The ability of the array to detect a wide range of neutron fluxes is highly advantageous for many applications such as detecting neutron flux during start up, ramp up and full power of nuclear reactors. 7 figs.

  10. Solid state neutron detector array

    DOE Patents [OSTI]

    Seidel, John G. (Pittsburgh, PA); Ruddy, Frank H. (Monroeville, PA); Brandt, Charles D. (Mount Lebanon, PA); Dulloo, Abdul R. (Pittsburgh, PA); Lott, Randy G. (Pittsburgh, PA); Sirianni, Ernest (Monroeville, PA); Wilson, Randall O. (Greensburg, PA)

    1999-01-01T23:59:59.000Z

    A neutron detector array is capable of measuring a wide range of neutron fluxes. The array includes multiple semiconductor neutron detectors. Each detector has a semiconductor active region that is resistant to radiation damage. In one embodiment, the array preferably has a relatively small size, making it possible to place the array in confined locations. The ability of the array to detect a wide range of neutron fluxes is highly advantageous for many applications such as detecting neutron flux during start up, ramp up and full power of nuclear reactors.

  11. Design, status and first operations of the spallation neutron source polyphase resonant converter modulator system

    SciTech Connect (OSTI)

    Reass, W. A. (William A.); Apgar, S. E. (Sean E.); Baca, D. M. (David M.); Doss, James D.; Gonzales, J. (Jacqueline); Gribble, R. F. (Robert F.); Hardek, T. W. (Thomas W.); Lynch, M. T. (Michael T.); Rees, D. E. (Daniel E.); Tallerico, P. J. (Paul J.); Trujillo, P. B. (Pete B.); Anderson, D. E. (David E.); Heidenreich, D. A. (Dale A.); Hicks, J. D. (Jim D.); Leontiev, V. N.

    2003-01-01T23:59:59.000Z

    The Spallation Neutron Source (SNS) is a new 1.4 MW average power beam, 1 GeV accelerator being built at Oak Ridge National Laboratory. The accelerator requires 15 converter-modulator stations each providing between 9 and 11 MW pulses with up to a 1 .I MW average power. The converter-modulator can be described as a resonant 20 kHz polyphase boost inverter. Each converter modulator derives its buss voltage from a standard substation cast-core transformer. Each substation is followed by an SCR pre-regulator to accommodate voltage changes from no load to full load, in addition to providing a soft-start function. Energy storage is provided by self-clearing metallized hazy polypropylene traction capacitors. These capacitors do not fail short, but clear any internal anomaly. Three 'H-Bridge' IGBT transistor networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are time-gated to generate the desired klystron pulse width. Pulse width modulation of the individual 20 lcHz pulses is utilized to provide regulated output waveforms with DSP based adaptive feedforward and feedback techniques. The boost transformer design utilizes nanocrystalline alloy that provides low core loss at design flux levels and switching frequencies. Capacitors are used on the transformer secondary networks to resonate the leakage inductance. The transformers are wound for a specific leakage inductance, not turns ratio. This design technique generates multiple secondary volts per turn as compared to the primary. With the appropriate tuning conditions, switching losses are minimized. The resonant topology has the added benefit of being deQed in a klystron fault condition, with little energy deposited in the arc. This obviates the need of crowbars or other related networks. A review of these design parameters, operational performance, production status, and OWL installation and performance to date will be presented.

  12. Federal Utility Partnership Working Group

    Broader source: Energy.gov [DOE]

    The Federal Utility Partnership Working Group (FUPWG) establishes partnerships and facilitates communications among Federal agencies, utilities, and energy service companies. The group develops strategies to implement cost-effective energy efficiency and water conservation projects through utility incentive programs at Federal sites.

  13. Dispute Resolution Process Utility Owner

    E-Print Network [OSTI]

    Minnesota, University of

    State One Call (GSOC) for "Design Call" Provide "as-builts", marked plans or field locates MnDOT Utility? Underground Utility? Contact Minnesota Office of Pipeline Safety Minnesota Office of Pipeline Safety Step 1 - Utility Identification for Construction Investigate and take appropriate action up to and including

  14. CONSORTIUM FOR CLEAN COAL UTILIZATION

    E-Print Network [OSTI]

    Subramanian, Venkat

    CONSORTIUM FOR CLEAN COAL UTILIZATION Call for Proposals Date of Issue: July 29, 2013 The Consortium for Clean Coal Utilization (CCCU) at Washington University in St. Louis was established in January of Clean Coal Utilization. The format may be a conference or workshop, or a seminar given by a leading

  15. STOCHASTIC COOLING OF BUNCHED BEAMS

    E-Print Network [OSTI]

    Bisognano, J.J.

    2010-01-01T23:59:59.000Z

    March 11-13, 1981 STOCHASTIC COOLING OF BUNCHED BEAMS J.J.W-7406-BW-48 STOCHASTIC COOLING OF BUNCHED BEAMS* J.J.longitudinal stochastic cooling of bunched particle beams.

  16. Cross-Section Measurements for (n,xn) Reactions by In-Beam Gamma-Ray Spectroscopy

    SciTech Connect (OSTI)

    Pavlik, A. [Institut fuer Isotopenforschung und Kernphysik, Universitaet Wien, Waehringer Str. 17, 1090 Vienna (Austria); Baumann, P.; Kerveno, M.; Rudolf, G. [Institut de Recherches Subatomiques, IN2P3, 23 rue du Loess, 67037 Strasbourg (France); Borcea, C.; Mihailescu, L.C. [EC-JRC Institute for Reference Materials and Measurements, Retieseweg 111, 2440 Geel (Belgium); 'Horia Hulubei' National Inst. for Physics and Nuclear Engineering, P.O. Box MG-6, 76900 Bucharest (Romania); Jericha, E.; Raskinyte, I. [Atominstitut der Oesterr, Universitaeten, Technische Universitaet Wien, Wiedner Hauptstr. 8-10, 1040 Vienna (Austria); Jokic, S.; Lukic, S. [Institut za nuklearne nauke Vinca, pp 522, 11001 Belgrade (Serbia and Montenegro); Meulders, J.P. [Institut de Physique Nucleaire, Universite Catholique de Louvain, Chemin du cyclotron 2, 1348 Louvain-la-Neuve (Belgium); Nolte, R. [Physikalisch-Technische Bundesanstalt, Postfach 3345, 38023 Braunschweig (Germany); Plompen, A.J.M. [EC-JRC Institute for Reference Materials and Measurements, Retieseweg 111, 2440 Geel (Belgium)

    2005-05-24T23:59:59.000Z

    The nuclear reactions 207Pb(n,2n)206Pb and 232Th(n,5n)228Th were studied by measuring prompt gamma-ray emission spectra from the interaction of neutrons with an enriched 207Pb sample and a natTh sample. For 207Pb the measurements were performed at the white neutron beam of the GELINA neutron source at IRMM Geel in the neutron energy range up to 20 MeV. The Th measurements were done at the quasi-monoenergetic 7Li(p,n)7Be neutron source at the Universite Catholique de Louvain for five peak neutron energies in the range 29 MeV to 42 MeV. The measurements were complemented by model calculations using the code system EMPIRE-II.

  17. Coated Fiber Neutron Detector Test

    SciTech Connect (OSTI)

    Lintereur, Azaree T.; Ely, James H.; Kouzes, Richard T.; Stromswold, David C.

    2009-10-23T23:59:59.000Z

    Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. The currently deployed radiation portal monitors (RPMs) from Ludlum and Science Applications International Corporation (SAIC) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large neutron detector. There is a declining supply of 3He in the world, and thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Reported here are the results of tests of the 6Li/ZnS(Ag)-coated non-scintillating plastic fibers option. This testing measured the required performance for neutron detection efficiency and gamma ray rejection capabilities of a system manufactured by Innovative American Technology (IAT).

  18. Characterization of Dosimetry of the BMRR Horizontal Thimble Tubes and Broad Beam Facility.

    SciTech Connect (OSTI)

    Hu,J.P.; Reciniello, R.N.; Holden, N.E.

    2008-05-05T23:59:59.000Z

    The Brookhaven Medical Research Reactor was a 5 mega-watt, light-water cooled and heavy-graphite moderated research facility. It has two shutter-equipped treatment rooms, three horizontally extended thimble tubes, and an ex-core broad beam facility. The three experimental thimbles, or activation ports, external to the reactor tank were designed for several uses, including the investigations on diagnostic and therapeutic methods using radioactive isotopes of very short half-life, the analysis of radiation exposure on tissue-equivalent materials using a collimated neutron beam, and the evaluation of dose effects on biological cells to improve medical treatment. At the broad beam facility where the distribution of thermal neutrons was essential uniform, a wide variety of mammalian whole-body exposures were studied using animals such as burros or mice. Also studied at the broad beam were whole-body phantom experiments, involving the use of a neutron or photon beam streaming through a screen to obtain the flux spectrum suitable for dose analysis on the sugar-urea-water mixture, a tissue-equivalent material. Calculations of the flux and the dose at beam ports based on Monte Carlo particle-transport code were performed, and measurements conducted at the same tally locations were made using bare or cadmium-covered gold foils. Analytical results, which show good agreement with measurement data, are presented in the paper.

  19. Energy Production Demonstrator for Megawatt Proton Beams

    E-Print Network [OSTI]

    Vitaly S. Pronskikh; Nikolai Mokhov; Igor Novitski; Sergey I. Tyutyunnikov

    2014-07-16T23:59:59.000Z

    A preliminary study of the Energy Production Demonstrator (EPD) concept - a solid heavy metal target irradiated by GeV-range intense proton beams and producing more energy than consuming - is carried out. Neutron production, fission, energy deposition, energy gain, testing volume and helium production are simulated with the MARS15 code for tungsten, thorium, and natural uranium targets in the proton energy range 0.5 to 120 GeV. This study shows that the proton energy range of 2 to 4 GeV is optimal for both a natU EPD and the tungsten-based testing station that would be the most suitable for proton accelerator facilities. Conservative estimates, not including breeding and fission of plutonium, based on the simulations suggest that the proton beam current of 1 mA will be sufficient to produce 1 GW of thermal output power with the natU EPD while supplying < 8% of that power to operate the accelerator. The thermal analysis shows that the concept considered has a problem due to a possible core meltdown; however, a number of approaches (a beam rastering, in first place) are suggested to mitigate the issue. The efficiency of the considered EPD as a Materials Test Station (MTS) is also evaluated in this study.

  20. Direct fissile assay of enriched uranium using random self-interrogation and neutron coincidence response

    DOE Patents [OSTI]

    Menlove, H.O.; Stewart, J.E.

    1985-02-04T23:59:59.000Z

    Apparatus and method for the direct, nondestructive evaluation of the /sup 235/U nuclide content of samples containing UF/sub 6/, UF/sub 4/, or UO/sub 2/ utilizing the passive neutron self-interrogation of the sample resulting from the intrinsic production of neutrons therein. The ratio of the emitted neutron coincidence count rate to the total emitted neutron count rate is determined and yields a measure of the bulk fissile mass. The accuracy of the method is 6.8% (1sigma) for cylinders containing UF/sub 6/ with enrichments ranging from 6% to 98% with measurement times varying from 3-6 min. The samples contained from below 1 kg to greater than 16 kg. Since the subject invention relies on fast neutron self-interrogation, complete sampling of the UF/sub 6/ takes place, reducing difficulties arising from inhomogeneity of the sample which adversely affects other assay procedures. 4 figs., 1 tab.