National Library of Energy BETA

Sample records for fundamental neutron physics

  1. Fundamental neutron physics at LANSCE

    SciTech Connect (OSTI)

    Greene, G.

    1995-10-01

    Modern neutron sources and science share a common origin in mid-20th-century scientific investigations concerned with the study of the fundamental interactions between elementary particles. Since the time of that common origin, neutron science and the study of elementary particles have evolved into quite disparate disciplines. The neutron became recognized as a powerful tool for studying condensed matter with modern neutron sources being primarily used (and justified) as tools for neutron scattering and materials science research. The study of elementary particles has, of course, led to the development of rather different tools and is now dominated by activities performed at extremely high energies. Notwithstanding this trend, the study of fundamental interactions using neutrons has continued and remains a vigorous activity at many contemporary neutron sources. This research, like neutron scattering research, has benefited enormously by the development of modern high-flux neutron facilities. Future sources, particularly high-power spallation sources, offer exciting possibilities for continuing this research.

  2. Ultra-cold neutron fundamental physics experiments at LANSCE...

    Office of Scientific and Technical Information (OSTI)

    Ultra-cold neutron fundamental physics experiments at LANSCE Citation Details In-Document Search Title: Ultra-cold neutron fundamental physics experiments at LANSCE Authors: Saunders, ...

  3. Final scientific and technical report for grant DE-AI02-93ER40784: Fundamental Physics with Cold Neutrons

    SciTech Connect (OSTI)

    Dewey, Maynard, S.

    2013-02-07

    There have been a growing number of notable results in fundamental neutron physics, which are briefly summarized.

  4. DOE Fundamentals Handbook: Classical Physics

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Classical Physics Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of physical forces and their properties. The handbook includes information on the units used to measure physical properties; vectors, and how they are used to show the net effect of various forces; Newton`s Laws of motion, and how to use these laws in force and motion applications; and the concepts of energy, work, and power, and how to measure and calculate the energy involved in various applications. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility systems and equipment.

  5. DOE Fundamentals Handbook: Classical Physics

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Classical Physics Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of physical forces and their properties. The handbook includes information on the units used to measure physical properties; vectors, and how they are used to show the net effect of various forces; Newton's Laws of motion, and how to use these laws in force and motion applications; and the concepts of energy, work, and power, and how to measure and calculate the energy involved in various applications. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility systems and equipment.

  6. Light particles A window to fundamental physics

    SciTech Connect (OSTI)

    Jaeckel, Joerg

    2010-08-30

    In these proceedings we illustrate that light, very weakly interacting particles can arise naturally from physics which is fundamentally connected to very high energy scales. Searching for them therefore may give us interesting new insights into the structure of fundamental physics. The prime example is the axion.

  7. DOE fundamentals handbook: Nuclear physics and reactor theory

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Nuclear Physics and Reactor Theory Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of nuclear physics and reactor theory. The handbook includes information on atomic and nuclear physics; neutron characteristics; reactor theory and nuclear parameters; and the theory of reactor operation. This information will provide personnel with a foundation for understanding the scientific principles that are associated with various DOE nuclear facility operations and maintenance.

  8. DOE fundamentals handbook: Nuclear physics and reactor theory. Volume 2

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Nuclear Physics and Reactor Theory Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of nuclear physics and reactor theory. The handbook includes information on atomic and nuclear physics; neutron characteristics; reactor theory and nuclear parameters; and the theory of reactor operation. This information will provide personnel with a foundation for understanding the scientific principles that are associated with various DOE nuclear facility operations and maintenance.

  9. DOE fundamentals handbook: Nuclear physics and reactor theory. Volume 1

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Nuclear Physics and Reactor Theory Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of nuclear physics and reactor theory. The handbook includes information on atomic and nuclear physics; neutron characteristics; reactor theory and nuclear parameters; and the theory of reactor operation. This information will provide personnel with a foundation for understanding the scientific principles that are associated with various DOE nuclear facility operations and maintenance.

  10. Dark Energy: A Crisis for Fundamental Physics

    ScienceCinema (OSTI)

    Stubbs, Christopher [Harvard University, Cambridge, Massachusetts, USA

    2010-09-01

    Astrophysical observations provide robust evidence that our current picture of fundamental physics is incomplete. The discovery in 1998 that the expansion of the Universe is accelerating (apparently due to gravitational repulsion between regions of empty space!) presents us with a profound challenge, at the interface between gravity and quantum mechanics. This "Dark Energy" problem is arguably the most pressing open question in modern fundamental physics. The first talk will describe why the Dark Energy problem constitutes a crisis, with wide-reaching ramifications. One consequence is that we should probe our understanding of gravity at all accessible scales, and the second talk will present experiments and observations that are exploring this issue.

  11. The nuclear physics of neutron stars

    SciTech Connect (OSTI)

    Piekarewicz, J.

    2014-05-09

    We explore the unique and fascinating structure of neutron stars. Although neutron stars are of interest in many areas of Physics, our aim is to provide an intellectual bridge between Nuclear Physics and Astrophysics. We argue against the naive perception of a neutron star as a uniform assembly of neutrons packed to enormous densities. Rather, by focusing on the many exotic phases that are speculated to exist in a neutron star, we show how the reality is different and far more interesting.

  12. Experiment Design and Analysis Guide - Neutronics & Physics

    SciTech Connect (OSTI)

    Misti A Lillo

    2014-06-01

    The purpose of this guide is to provide a consistent, standardized approach to performing neutronics/physics analysis for experiments inserted into the Advanced Test Reactor (ATR). This document provides neutronics/physics analysis guidance to support experiment design and analysis needs for experiments irradiated in the ATR. This guide addresses neutronics/physics analysis in support of experiment design, experiment safety, and experiment program objectives and goals. The intent of this guide is to provide a standardized approach for performing typical neutronics/physics analyses. Deviation from this guide is allowed provided that neutronics/physics analysis details are properly documented in an analysis report.

  13. Bridging the Gap between Fundamental Physics and Chemistry and Applied

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

    Models for HCCI Engines | Department of Energy Bridging the Gap between Fundamental Physics and Chemistry and Applied Models for HCCI Engines Bridging the Gap between Fundamental Physics and Chemistry and Applied Models for HCCI Engines 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005_deer_assanis.pdf (1.42 MB) More Documents & Publications Computationally Efficient Modeling of High-Efficiency Clean Combustion Engines Modeling of HCCI and PCCI

  14. Nuclear Physics: The Ultracold Neutron Source (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Nuclear Physics: The Ultracold Neutron Source Citation Details In-Document Search Title: Nuclear Physics: The Ultracold Neutron Source Authors: Kippen, Karen E. 1 ; Clayton, ...

  15. Nuclear Physics: The Ultracold Neutron Source (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Nuclear Physics: The Ultracold Neutron Source Citation Details In-Document Search Title: Nuclear Physics: The Ultracold Neutron Source Authors: Kippen, Karen E. ...

  16. Nuclear Physics: The Ultracold Neutron Source (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Nuclear Physics: The Ultracold Neutron Source Citation Details In-Document Search Title: Nuclear Physics: The Ultracold Neutron Source You are accessing a ...

  17. COLLOQUIUM: Fundamental Physics and the LHC: A Progress Report | Princeton

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

    Plasma Physics Lab 17, 2013, 4:15pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: Fundamental Physics and the LHC: A Progress Report Professor Nima Arkani-Hamed The Institute for Advanced Study Presentation: PDF icon WC17APR2013_NAHamed.pdf Last July's discovery of the Higgs particle at the Large Hadron Collider was a triumph for both experiment and theory in fundamental physics. But the Higgs also introduces major conceptual paradoxes that strongly suggest we are missing essential new

  18. Caltech announces discovery in fundamental physics | Argonne National

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

    Laboratory Caltech announces discovery in fundamental physics August 18, 2015 Tweet EmailPrint This press release was originally printed by CalTech. When the transistor was invented in 1947 at Bell Labs, few could have foreseen the future impact of the device. This fundamental development in science and engineering was critical to the invention of handheld radios, led to modern computing, and enabled technologies such as the smartphone. This is one of the values of basic research. In a

  19. Fermilab | Science | Particle Physics | More fundamental particles and

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

    forces More fundamental particles and forces Fermilab is America's premier national laboratory for particle physics research. Particle physicists seek to understand the very building blocks of our universe-the smallest bits of matter and how they interact. Experiments at Fermilab use cutting-edge accelerator and detector technology to learn the secrets of these elementary particles and forces. For decades, thousands of scientists from universities and laboratories around the world have

  20. Fundamental

    Office of Scientific and Technical Information (OSTI)

    TID-267 11-P2 '4 ' Fundamental Aspects of Nuclear Reactor Fuel Elements Solutions to Problems Donald R. Olander Department - of Nuclear Engineering University of Cacfornia, ...

  1. DOE-HDBK-1019/1-93; DOE Fundamentals Handbook Nuclear Physics...

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

    ... NEUTRON INTERACTIONS DOE-HDBK-10191-93 Atomic and Nuclear Physics NP-01 Page 46 Rev. 0 ... in the loss of a neutron coupled with the production of a charged particle or gamma ray. ...

  2. Nuclear Physics: The Ultracold Neutron Source Kippen, Karen E...

    Office of Scientific and Technical Information (OSTI)

    Physics: The Ultracold Neutron Source Kippen, Karen E. Los Alamos National Laboratory Los Alamos National Laboratory; Clayton, Steven Los Alamos National Laboratory Los...

  3. Evaluated Neutron Nuclear Data for Reactor Physics Calculations.

    Energy Science and Technology Software Center (OSTI)

    1988-09-15

    Version 00 The data file KEDAK contains the evaluated neutron nuclear data for a number of materials important for the reactor physics, specific physical experiments, burn up calculations, shielding and other applications.

  4. Synopsis: Getting Under the Neutron Skin (Physics) | Jefferson Lab

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

    Synopsis: Getting Under the Neutron Skin (Physics) External Link: http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.108.112502 By jlab_admin on Thu, 2012-03-15

  5. Reconstruction of local neutron physical functionals in surface harmonics method

    SciTech Connect (OSTI)

    Boyarinov, V. F. Nevinitsa, V. A.

    2010-12-15

    Formulas for reconstruction of local neutron physical functionals for a three-stage calculation of a 2D VVER-1000 core using the surface harmonics method are obtained, implemented in the SUHAM code, and verified.

  6. Fundamentals of health physics for the radiation-protection officer

    SciTech Connect (OSTI)

    Murphy, B.L.; Traub, R.J.; Gilchrist, R.L.; Mann, J.C.; Munson, L.H.; Carbaugh, E.H.; Baer, J.L.

    1983-03-01

    The contents of this book on health physics include chapters on properties of radioactive materials, radiation instrumentation, radiation protection programs, radiation survey programs, internal exposure, external exposure, decontamination, selection and design of radiation facilities, transportation of radioactive materials, radioactive waste management, radiation accidents and emergency preparedness, training, record keeping, quality assurance, and appraisal of radiation protection programs. (ACR)

  7. Neutron Electric Dipole Moments from Beyond the Standard Model Physics

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Conference: Neutron Electric Dipole Moments from Beyond the Standard Model Physics Citation Details In-Document Search Title: Neutron Electric Dipole Moments from Beyond the Standard Model Physics Authors: Bhattacharya, Tanmoy [1] ; Cirigliano, Vincenzo [1] ; Gupta, Rajan [1] + Show Author Affiliations Los Alamos National Laboratory Publication Date: 2013-11-18 OSTI Identifier: 1107163 Report Number(s): LA-UR-13-28859 DOE Contract Number: AC52-06NA25396

  8. Neutron stars as laboratories for gravity physics

    SciTech Connect (OSTI)

    Deliduman, Cemsinan

    2014-01-01

    We study the structure of neutron stars in R+?R gravity model with perturbative method. We obtain mass-radius relations for four representative equations of state (EoS). We find that, for |?|~10? cm, the results differ substantially from the results of general relativity. The effects of modified gravity are seen as mimicking a stiff or soft EoS for neutron stars depending upon whether ? is negative or positive, respectively. Some of the soft EoS that are excluded within the framework of general relativity can be reconciled for certain values of ? of this order with the 2 solar mass neutron star recently observed. Indeed, if the EoS is ever established to be soft, modified gravity of the sort studied here may be required to explain neutron star masses as large as 2 M{sub ?}. The associated length scale ?(?)~10? cm is of the order of the the typical radius of neutron stars implying that this is the smallest value we could find by using neutron stars as a probe. We thus conclude that the true value of ? is most likely much smaller than 10? cm.

  9. Fundamental physics at the intensity frontier. Report of the workshop held December 2011 in Rockville, MD.

    SciTech Connect (OSTI)

    Hewett, J.L.; Weerts, H.; Brock, R.; Butler, J.N.; Casey, B.C.K.; Lu, Z.T.; Wagner, C.E.M.; Dietrich, M.R.; Djurcic, Z.; Goodman, M.; Green, J.P.; Holt, R.J.; Mueller, P.; Paley, J.; Reimer, P.; Singh, J.; Upadhye, A.

    2012-06-05

    Particle physics aims to understand the universe around us. The Standard Model of particle physics describes the basic structure of matter and forces, to the extent we have been able to probe thus far. However, it leaves some big questions unanswered. Some are within the Standard Model itself, such as why there are so many fundamental particles and why they have different masses. In other cases, the Standard Model simply fails to explain some phenomena, such as the observed matter-antimatter asymmetry in the universe, the existence of dark matter and dark energy, and the mechanism that reconciles gravity with quantum mechanics. These gaps lead us to conclude that the universe must contain new and unexplored elements of Nature. Most of particle and nuclear physics is directed towards discovering and understanding these new laws of physics. These questions are best pursued with a variety of approaches, rather than with a single experiment or technique. Particle physics uses three basic approaches, often characterized as exploration along the cosmic, energy, and intensity frontiers. Each employs different tools and techniques, but they ultimately address the same fundamental questions. This allows a multi-pronged approach where attacking basic questions from different angles furthers knowledge and provides deeper answers, so that the whole is more than a sum of the parts. A coherent picture or underlying theoretical model can more easily emerge, to be proven correct or not. The intensity frontier explores fundamental physics with intense sources and ultra-sensitive, sometimes massive detectors. It encompasses searches for extremely rare processes and for tiny deviations from Standard Model expectations. Intensity frontier experiments use precision measurements to probe quantum effects. They typically investigate very large energy scales, even higher than the kinematic reach of high energy particle accelerators. The science addresses basic questions, such as: Are there

  10. Neutron skins and neutron stars

    SciTech Connect (OSTI)

    Piekarewicz, J.

    2013-11-07

    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.

  11. Probing TeV physics in the structure of the neutron (Technical...

    Office of Scientific and Technical Information (OSTI)

    Probing TeV physics in the structure of the neutron Citation Details In-Document Search Title: Probing TeV physics in the structure of the neutron You are accessing a document ...

  12. COLLOQUIUM: Type II Solar Radio Bursts: From Fundamental Plasma Physics to

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

    Space Weather Research | Princeton Plasma Physics Lab April 8, 2015, 4:15pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: Type II Solar Radio Bursts: From Fundamental Plasma Physics to Space Weather Research Professor Iver Cairns University of Sydney - School of Physics Presentation: File WC08APR2015_ICairns_4.pptx For over 60 years type II solar radio bursts have defied detailed quantitative explanation, despite their promise for predicting space weather at Earth and their status as the

  13. A Large-Area Detector for Fundamental Neutron Science | U.S....

    Office of Science (SC) Website

    ... Seestrom, E. I. Sharapov, A. Sprow, Z. Tang, W. Wei, J. W. Wexler, T. L. Womack, A. R. Young, and B. A. Zeck, "A Multilayer Surface Detector for Ultracold Neutrons External link ." ...

  14. DOE-HDBK-1010-92; Doe Fundamentals Handbook Classical Physics

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

    0-92 JUNE 1992 DOE FUNDAMENTALS HANDBOOK CLASSICAL PHYSICS U.S. Department of Energy FSC-6910 Washington, D.C. 20585 Distribution Statement A. Approved for public release; distribution is unlimited. This document has been reproduced directly from the best available copy. Available to DOE and DOE contractors from the Office of Scientific and Technical Information. P. O. Box 62, Oak Ridge, TN 37831; (615) 576-8401. Available to the public from the National Technical Information Service, U.S.

  15. Neutrinos: an Open Window on Fundamental Physics and the Evolution of the Universe

    SciTech Connect (OSTI)

    Pascoli, Silvia

    2010-08-18

    In the past ten years, a series of experiments has confirmed that neutrinos can oscillate between different types ('flavors') and have mass. These results are the first solid evidence for physics beyond the Standard Model of Particle Physics, with profound implications for the Universe and the laws that govern it. Thanks to a broad experimental program, including accelerator- and reactor-based experiments such as MINOS, MiniBooNE, T2K, Double-CHOOZ, Daya Bay, NOvA, LBNE, and searches for neutrinoless double beta decay, we have just entered the 'precision era' in neutrino physics. I will review the status of experimental results, their implications for our understanding of neutrino properties, and the questions that must be addressed. I will give an overview of the exciting experimental program that is underway and I will discuss how neutrino physics will help in opening a new window on the fundamental laws of Nature, its fundamental constituents, and the evolution of the Universe.

  16. Probing TeV physics in the structure of the neutron (Technical...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Probing TeV physics in the structure of the neutron Citation Details ... Sponsoring Org: LDRD; USDOE Country of Publication: United States Language: English ...

  17. Neutron detector

    DOE Patents [OSTI]

    Stephan, Andrew C.; Jardret; Vincent D.

    2011-04-05

    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.

  18. DOE-HDBK-1019/2-93; DOE Fundamentals Handbook Nuclear Physics...

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

    ... However, in a heterogeneous reactor, all the fuel atoms are packed closely together in elements such as pins, rods, or pellets. Neutrons emitted from the fission of one fuel atom ...

  19. Nuclear Physics: The Ultracold Neutron Source (Technical Report) | SciTech

    Office of Scientific and Technical Information (OSTI)

    Connect Technical Report: Nuclear Physics: The Ultracold Neutron Source Citation Details In-Document Search Title: Nuclear Physics: The Ultracold Neutron Source Authors: Kippen, Karen E. [1] ; Clayton, Steven [1] + Show Author Affiliations Los Alamos National Laboratory Publication Date: 2014-04-10 OSTI Identifier: 1127473 Report Number(s): LA-UR-14-22440 DOE Contract Number: AC52-06NA25396 Resource Type: Technical Report Research Org: Los Alamos National Laboratory (LANL) Sponsoring Org:

  20. Basic Physics Data: Measurement of Neutron Multiplicity from Induced Fission

    SciTech Connect (OSTI)

    Pozzi, Sara; Haight, Robert

    2015-05-04

    From October 1 to October 17 a team of researchers from UM visited the LANSCE facility for an experiment during beam-time allotted from October 4 to October 17. A total of 24 detectors were used at LANSCE including liquid organic scintillation detectors (EJ-309), NaI scintillation detectors, and Li-6 enriched glass detectors. It is a double time-offlight (TOF) measurement using spallation neutrons generated by a target bombarded with pulsed high-energy protons. The neutrons travel to an LLNL-manufactured parallel plate avalanche chamber (PPAC) loaded with thin U-235 foils in which fission events are induced. The generated fission neutrons and photons are then detected in a detector array designed and built at UM and shipped to LANSCE. Preparations were made at UM, where setup and proposed detectors were tested. The UM equipment was then shipped to LANSCE for use at the 15L beam of the weapons neutron research (WNR) facility.

  1. Intense fusion neutron sources

    SciTech Connect (OSTI)

    Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

    2010-04-15

    The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 10{sup 15}-10{sup 21} neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 10{sup 20} neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the

  2. Reactor physics analyses of the advanced neutron source three-element core

    SciTech Connect (OSTI)

    Gehin, J.C.

    1995-08-01

    A reactor physics analysis was performed for the Advanced Neutron Source reactor with a three-element core configuration. The analysis was performed with a two-dimensional r-z 20-energy-group finite-difference diffusion theory model of the 17-d fuel cycle. The model included equivalent r-z geometry representations of the central control rods, the irradiation and production targets, and reflector components. Calculated quantities include fuel cycle parameters, fuel element power distributions, unperturbed neutron fluxes in the reflector and target regions, reactivity perturbations, and neutron kinetics parameters.

  3. Radiological and Environmental Research Division annual report, October 1979-September 1980: fundamental molecular physics and chemistry

    SciTech Connect (OSTI)

    Inokuti, Mitio; Dehmer, P. M.; Pratt, S. T.; Poliakoff, E. D.; Dehmer, J. L.; Stockbauer, Roger; Dill, Dan; Parr, A. C.; Jackson, K. H.; Zare, R. N.; Person, J. C.; Nicole, P. P.; Fowler, D. E.; Codling, K.; West, J. B.; Ederer, D. L.; Cole, B. E.; Loomba, D.; Wallace, Scott; Swanson, J. R.; Poliakoff, E. D.; Spence, David; Chupka, W. A.; Stevens, C. M.; Shyn, W. T.; Sharp, W. E.; Kim, Y. K.; Eggarter, E.; Baer, T.; Hanson, J. D.; Shimamura, Isao; Dillon, Michael A.

    1981-09-01

    Research is reported on the physics and chemistry of atoms, ions, and molecules, especially their interactions with external agents such as photons and electrons. Individual items from the report were prepared separately for the data base. (GHT)

  4. Black Holes in the Cosmos, the Lab, and in Fundamental Physics (3/3)

    ScienceCinema (OSTI)

    None

    2011-10-06

    Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

  5. Black Holes in the Cosmos, the Lab, and in Fundamental Physics (2/3)

    ScienceCinema (OSTI)

    None

    2011-10-06

    Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

  6. Black Holes in the Cosmos, the Lab, and in Fundamental Physics (1/3)

    ScienceCinema (OSTI)

    None

    2011-10-06

    Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

  7. Fundamental Magnetofluid Physics Studies on the Swarthmore Spheromak Experiment: Reconnection and Sustainment

    SciTech Connect (OSTI)

    Brown, M.R.

    2001-07-31

    The general goal of the Magnetofluids Laboratory at Swarthmore College is to understand how magnetofluid kinetic energy can be converted to magnetic energy as it is in the core of the earth and sun (the dynamo problem) and to understand how magnetic energy can be rapidly converted back to kinetic energy and heat as it is in solar flares (the magnetic reconnection problem). Magnetic reconnection has been studied using the Swarthmore Spheromak Experiment (SSX) which was designed and built under this Junior Faculty Grant. In SSX we generate and merge two rings of magnetized plasma called spheromaks and study their interaction. The spheromaks have many properties similar to solar flares so this work is directly relevant to basic solar physics. In addition, since the spheromak is a magnetic confinement fusion configuration, issues of formation and stability have direct impact on the fusion program.

  8. The {beta}{sup +} decay of {sup 37}K as a multi-faceted probe of fundamental physics

    SciTech Connect (OSTI)

    Melconian, D.; Mehlman, M.; Behling, R. S.; Behr, J. A.; Gorelov, A.; Jackson, K. P.; Kong, T.; Pearson, M. R.; Ashery, D.; Shidling, P.

    2011-06-28

    Precision {beta} decay experiments represent an important and complimentary approach to high-energy searches for physics outside the ''Standard Model'', our current understanding of fundamental particles and their interactions. The mirror decay of {sup 37}K provides an excellent probe with which to search for new physics. The ft value of this (as well as other T = 1/2 mirror transitions) can be used to provide a measurement of the value of the V{sub ud} element of the CKM mass-mixing matrix, complementing the value obtained from superallowed pure Fermi decays. In addition, the polarized angular distribution parameters are sensitive to a variety of possible new physics: the {beta} and {nu} asymmetries can be used to search for right-handed currents in the charged weak interaction, and their energy-dependences are sensitive to second-class currents forbidden in the Standard Model. Time-reversal symmetry can also be tested by a precision measurement of the triple-vector correlation between the initial nuclear spin and the momenta of the leptons. An overview of the variety of physics that can be probed using laser-cooled {sup 37}K and the techniques used to perform the precision measurements is presented.

  9. New precision measurements of free neutron beta decay with cold neutrons

    SciTech Connect (OSTI)

    Baeßler, Stefan; Bowman, James David; Penttilä, Seppo I.; Počanić, Dinko

    2014-10-14

    Precision measurements in free neutron beta decay serve to determine the coupling constants of beta decay, and offer several stringent tests of the standard model. This study describes the free neutron beta decay program planned for the Fundamental Physics Beamline at the Spallation Neutron Source at Oak Ridge National Laboratory, and finally puts it into the context of other recent and planned measurements of neutron beta decay observables.

  10. Three-Dimensional Few-Group Coarse Mesh Diffusion Code for Neutron Physics Calculation of Reactor Core in Hexagonal Geometry.

    Energy Science and Technology Software Center (OSTI)

    1991-10-01

    Version 00 HEXAB-3D solves the three-dimensional few-group diffusion model for the calculation of the basic neutron physical characteristics of power reactors in hexagonal geometry.

  11. Physics

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

    Physics Physics Print Because a large proportion of ALS experiments are "physics" experiments, it's useful to separate them into two categories - one focused on Materials/Condensed Matter, and this one, with a dual focus on AMO (atomic, molecular, and optical) physics and accelerator physics. Light sources such as the ALS have opened up research frontiers that may hold the answers to fundamental questions about structure and dynamics in AMO physics. The advanced spectroscopies that

  12. Neutron Physics. A Revision of I. Halpern's notes on E. Fermi's lectures in 1945

    DOE R&D Accomplishments [OSTI]

    Beckerley, J.G.

    1951-10-16

    In the Fall of 1945 a course in Neutron Physics was given by Professor Fermi as part of the program of the Los Alamos University. The course consisted of thirty lectures most of which were given by Fermi. In his absence R.F. Christy and E. Segre gave several lectures. The present revision is based upon class notes prepared by I. Halpern with some assistance by B.T. Feld and issued first as document LADC 255 and later with wider circulation as MDDC 320.

  13. Physics

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

    Physics Print Because a large proportion of ALS experiments are "physics" experiments, it's useful to separate them into two categories - one focused on Materials/Condensed Matter, and this one, with a dual focus on AMO (atomic, molecular, and optical) physics and accelerator physics. Light sources such as the ALS have opened up research frontiers that may hold the answers to fundamental questions about structure and dynamics in AMO physics. The advanced spectroscopies that have been

  14. Physics

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

    Physics Physics Our science answers questions about the nature of the universe and delivers solutions for national security concerns. Contact Us Division Leader David Meyerhofer Deputy Division Leader Scott Wilburn Division Office (505) 667-4117 For more than 70 years-from the Manhattan Project to today-Physics Division researchers have been performing groundbreaking fundamental and applied research. For more than 70 years-from the Manhattan Project to today-Physics Division researchers have

  15. Collaborative Physical and Biological Dosimetry Studies for Neutron Capture Therapy at the RA-1 Research Reactor Facility

    SciTech Connect (OSTI)

    David W. Nigg; Amanda E. Schwint; John K. Hartwell; Elisa M. Heber; Veronica Trivillin; Jorge Castillo; Luis Wentzeis; Patrick Sloan; Charles A. Wemple

    2004-10-01

    Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminiscent dosimeters to characterize the BNCT irradiation facility developed at the RA-1 research reactor operated by the Argentine National Atomic Energy Commission in Buenos Aires. Some biological scoping irradiations have also been completed using a small-animal (hamster) oral mucosa tumor model. Results indicate that the RA-1 neutron source produces useful dose rates but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications.

  16. Fundamentals of a modified model of the distribution of neutron-resonance widths and results of its application in the mass-number range of 35 {<=} A {<=} 249

    SciTech Connect (OSTI)

    Sukhovoj, A. M. Khitrov, V. A.

    2013-01-15

    A modified model is developed for describing the distribution of random resonance width for any nuclei. The model assumes the coexistence in a nucleus of one or several partial radiative and neutron amplitudes for respective resonance widths, these amplitudes differing in their parameters. Also, it is assumed that amplitude can be described by a Gaussian curve characterized by a nonzero mean value and a variance not equal to unity and that their most probable values can be obtained with the highest reliability from approximations of cumulative sums of respective widths. An analysis of data for 157 sets of neutron widths for 0 {<=} l {<=} 3 and for 56 sets of total radiative widths has been performed to date. The basic result of this analysis is the following: both for neutron and for total radiative widths, the experimental set of resonance width can be represented with a rather high probability in the form of a superposition of k {<=} 4 types differing in mean amplitude parameters.

  17. Improving Neutron Measurement Capabilities; Expanding the Limits of Correlated Neutron Counting

    SciTech Connect (OSTI)

    Santi, Peter Angelo; Geist, William H.; Dougan, Arden

    2015-11-05

    A number of technical and practical limitations exist within the neutron correlated counting techniques used in safeguards, especially within the algorithms that are used to process and analyze the detected neutron signals. A multi-laboratory effort is underway to develop new and improved analysis and data processing algorithms based on fundamental physics principles to extract additional or more accurate information about nuclear material bearing items.

  18. Theory of Neutron Chain Reactions: Extracts from Volume I, Diffusion and Slowing Down of Neutrons: Chapter I. Elementary Theory of Neutron Diffusion. Chapter II. Second Order Diffusion Theory. Chapter III. Slowing Down of Neutrons

    DOE R&D Accomplishments [OSTI]

    Weinberg, Alvin M.; Noderer, L. C.

    1951-05-15

    The large scale release of nuclear energy in a uranium fission chain reaction involves two essentially distinct physical phenomena. On the one hand there are the individual nuclear processes such as fission, neutron capture, and neutron scattering. These are essentially quantum mechanical in character, and their theory is non-classical. On the other hand, there is the process of diffusion -- in particular, diffusion of neutrons, which is of fundamental importance in a nuclear chain reaction. This process is classical; insofar as the theory of the nuclear chain reaction depends on the theory of neutron diffusion, the mathematical study of chain reactions is an application of classical, not quantum mechanical, techniques.

  19. Low Temperature and Neutron Physics Studies: Final Progress Report, March 1, 1986--May 31, 1987

    DOE R&D Accomplishments [OSTI]

    Shull, C.G.

    1989-07-27

    A search for a novel coupling interaction between the Pendelloesung periodicity which is formed in a diffracting crystal and the Larmor precession of neutrons in a magnetic field has been carried out. This interaction is expected to exhibit a resonant behavior when the two spatial periodicities become matched upon scanning the magnetic field being applied to the crystal. Observations on a diffracting, perfect crystal of silicon with neutrons of wavelength 1 Angstrom show the expected resonant action but some discrepancy between the observed magnitude of the resonance effects remains for interpretation.

  20. Relevance of β-delayed neutron data for reactor, nuclear physics and astrophysics applications

    SciTech Connect (OSTI)

    Kratz, Karl-Ludwig

    2015-02-24

    Initially, yields (or abundances) and branching ratios of β-delayed neutrons (βdn) from fission products (P{sub n}-values) have had their main importance in nuclear reactor control. At that time, the six-group mathematical approximation of the time-dependence of βdn-data in terms of the so-called 'Keepin groups' was generally accepted. Later, with the development of high-resolution neutron spectroscopy, βdn data have provided important information on nuclear-structure properties at intermediate excitation energy in nuclei far from stability, as well as in nuclear astrophysics. In this paper, I will present some examples of the βdn-studies performed by the Kernchemie Mainz group during the past three decades. This work has been recognized as an example of 'broad scientific diversity' which has led to my nomination for the 2014 Hans A. Bethe prize.

  1. Advancing Materials Science using Neutrons at Oak Ridge National Laboratory

    ScienceCinema (OSTI)

    Carpenter, John

    2014-06-03

    Jack Carpenter, pioneer of accelerator-based pulsed spallation neutron sources, talks about neutron science at Oak Ridge National Laboratory (ORNL) and a need for a second target station at the Spallation Neutron Source (SNS). ORNL is the Department of Energy's largest multiprogram science and energy laboratory, and is home to two scientific user facilities serving the neutron science research community: the High Flux Isotope Reactor (HFIR) and SNS. HFIR and SNS provide researchers with unmatched capabilities for understanding the structure and properties of materials, macromolecular and biological systems, and the fundamental physics of the neutron. Neutrons provide a window through which to view materials at a microscopic level that allow researchers to develop better materials and better products. Neutrons enable us to understand materials we use in everyday life. Carpenter explains the need for another station to produce long wavelength neutrons, or cold neutrons, to answer questions that are addressed only with cold neutrons. The second target station is optimized for that purpose. Modern technology depends more and more upon intimate atomic knowledge of materials, and neutrons are an ideal probe.

  2. Spatial corrections for pulsed-neutron reactivity measurements.

    SciTech Connect (OSTI)

    Cao, Y.; Lee, J.; Nuclear Engineering Division; Univ. of Michigan

    2010-07-01

    For pulsed-neutron experiments performed in a subcritical reactor, the reactivity obtained from the area-ratio method is sensitive to detector positions. The spatial effects are induced by the presence of both the prompt neutron harmonics and the delayed neutron harmonics in the reactor. The traditional kinetics distortion factor is only limited to correcting the spatial effects caused by the fundamental prompt-{alpha} mode. In this paper, we derive spatial correction factors fp and fd to account for spatial effects induced by the prompt neutron harmonics and the delayed neutron harmonics, respectively. Our numerical simulations with the FX2-TH time-dependent multigroup diffusion code indicate that the high-order prompt neutron harmonics lead to significant spatial effects and cannot be neglected in calculating the spatial correction factors. The prompt spatial correction factor fp can be simply determined by the ratio of the normalized detector responses corresponding to the fundamental k-mode and the prompt neutron flux integrated over the pulse period. Thus, it is convenient to calculate and provides physically intuitive explanations on the spatial dependence of reactivity measured in the MUSE-4 experiments: overestimation of the subcriticality in regions close to the external neutron source and underestimation of the subcriticality away from the source but within the fuel region.

  3. SNS nEDM | Ultracold Neutrons at Los Alamos National Laboratory (pRad)

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

    SNS nEDM An electric dipole moment (EDM) measures the separation of positive and negative charges within a system and is an extremely sensitive probe of physics beyond the standard model. A new neutron EDM (nEDM) experiment is being developed to be installed at the Fundamental Neutron Physics Beamline (FnPB) at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, with a goal sensitivity of δdn~5 x10-28 e-cm, an improvement of two orders of magnitude over the current limit set

  4. A short note on physical properties to irradiated nuclear fuel by means of X-ray diffraction and neutron scattering techniques

    SciTech Connect (OSTI)

    Abdullah, Yusof Husain, Hishamuddin; Hak, Cik Rohaida Che; Alias, Nor Hayati; Yusof, Mohd Reusmaazran; Kasim, Norasiah Ab; Zali, Nurazila Mat; Mohamed, Abdul Aziz

    2015-04-29

    For nuclear reactor applications, understanding the evolution of the fuel materials microstructure during irradiation are of great importance. This paper reviews the physical properties of irradiated nuclear fuel analysis which are considered to be of most importance in determining the performance behavior of fuel. X-rays diffraction was recognize as important tool to investigate the phase identification while neutron scattering analyses the interaction between uranium and other materials and also investigation of the defect structure.

  5. Neutron physics of the Re/Os clock. II. The (n,n{sup '}) cross section of {sup 187}Os at 30 keV neutron energy

    SciTech Connect (OSTI)

    Mosconi, M.; Heil, M.; Kaeppeler, F.; Plag, R.; Mengoni, A.

    2010-07-15

    The inelastic neutron-scattering cross section of {sup 187}Os has been determined in a time-of-flight experiment at the Karlsruhe 3.7-MV Van de Graaff accelerator. An almost monoenergetic beam of 30-keV neutrons was produced at the threshold of the {sup 7}Li(p,n){sup 7}Be reaction. Information on the inelastic channel is required for reliable calculations of the so-called stellar enhancement factor, by which the laboratory cross section of {sup 187}Os must be corrected in order to account for the thermal population of low-lying excited states at the temperatures of s-process nucleosynthesis, in particular of the important state at 9.75 keV. This correction represents a crucial step in the interpretation of the {sup 187}Os/{sup 187}Re pair as a cosmochronometer.

  6. Neutronic reactor

    DOE Patents [OSTI]

    Carleton, John T.

    1977-01-25

    A graphite-moderated nuclear reactor includes channels between blocks of graphite and also includes spacer blocks between adjacent channeled blocks with an axis of extension normal to that of the axis of elongation of the channeled blocks to minimize changes in the physical properties of the graphite as a result of prolonged neutron bombardment.

  7. Physics

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

    Group (PDG) Organizations American Institute of Physics (AIP) American Physical Society (APS) Institute of Physics (IOP) SPIE - International society for optics and photonics Top...

  8. Method of assaying uranium with prompt fission and thermal neutron borehole logging adjusted by borehole physical characteristics. [Patient application

    DOE Patents [OSTI]

    Barnard, R.W.; Jensen, D.H.

    1980-11-05

    Uranium formations are assayed by prompt fission neutron logging techniques. The uranium in the formation is proportional to the ratio of epithermal counts to thermal or epithermal dieaway. Various calibration factors enhance the accuracy of the measurement.

  9. Method of assaying uranium with prompt fission and thermal neutron borehole logging adjusted by borehole physical characteristics

    DOE Patents [OSTI]

    Barnard, Ralston W.; Jensen, Dal H.

    1982-01-01

    Uranium formations are assayed by prompt fission neutron logging techniques. The uranium in the formation is proportional to the ratio of epithermal counts to thermal or eqithermal dieaway. Various calibration factors enhance the accuracy of the measurement.

  10. Clifford G. Shull, Neutron Diffraction, Hydrogen Atoms, and Neutron...

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

    ... Laue Photography of Neutron Diffraction; Physical Review, Vol 73, Issue 5, 527-528, March 1, 1948 The Crystal Structure of Thorium and Zirconium Dihydrides by X-ray and Neutron ...

  11. HCCI/SCCI Fundamentals

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

    HCCISCCI Fundamentals - Sandia Energy Energy Search Icon Sandia Home Locations ... Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing ...

  12. Fundamental Science Applications

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

    Fundamental Science Applications Fundamental Science Applications Supporing research to understand, predict and ultimately control matter and energy at the electronic, atomic, and molecular levels. Contact thumbnail of Business Development Executive Don Hickmott Business Development Executive Richard P. Feynman Center for Innovation (505) 667-8753 Email Fundamental Science Applications The DOE Basic Energy Science (BES) program supports research to understand, predict and ultimately control

  13. High precision thermal neutron detectors

    SciTech Connect (OSTI)

    Radeka, V.; Schaknowski, N.A.; Smith, G.C.; Yu, B.

    1994-12-31

    Two-dimensional position sensitive detectors are indispensable in neutron diffraction experiments for determination of molecular and crystal structures in biology, solid-state physics and polymer chemistry. Some performance characteristics of these detectors are elementary and obvious, such as the position resolution, number of resolution elements, neutron detection efficiency, counting rate and sensitivity to gamma-ray background. High performance detectors are distinguished by more subtle characteristics such as the stability of the response (efficiency) versus position, stability of the recorded neutron positions, dynamic range, blooming or halo effects. While relatively few of them are needed around the world, these high performance devices are sophisticated and fairly complex, their development requires very specialized efforts. In this context, we describe here a program of detector development, based on {sup 3}He filled proportional chambers, which has been underway for some years at the Brookhaven National Laboratory. Fundamental approaches and practical considerations are outlined that have resulted in a series of high performance detectors with the best known position resolution, position stability, uniformity of response and reliability over time, for devices of this type.

  14. 2009 International Conference on Neutron Scattering (ICNS 2009)

    SciTech Connect (OSTI)

    Gopal Rao, PhD; Gillespie, Donna

    2010-08-05

    The ICNS provides a focal point for the worldwide neutron user community to strengthen ties within this diverse group, while at the same time promoting neutron research among colleagues in related disciplines identified as would-be neutron users. The International Conference on Neutron Scattering thus serves a dual role as an international user meeting and a scientific meeting. As a venue for scientific exchange, the ICNS showcases recent results and provides forums for scientific discussion of neutron research in diverse fields such as hard and soft condensed matter, liquids, biology, magnetism, engineering materials, chemical spectroscopy, crystal structure, and elementary excitations, fundamental physics and development of neutron instrumentation through a combination of invited talks, contributed talks and poster sessions. Each of the major national neutron facilities (NIST, LANSCE, ANL, HFIR and SNS), along with their international counterparts, has an opportunity to exchange information with each other and to update users, and potential users, of their facility. This is also an appropriate forum for users to raise issues that relate to the facilities.

  15. Focusing adaptive-optics for neutron spectroscopy at extreme conditions

    SciTech Connect (OSTI)

    Simeoni, G. G.; Valicu, R. G.; Borchert, G.; Böni, P.; Rasmussen, N. G.; Yang, F.; Kordel, T.; Holland-Moritz, D.; Kargl, F.; Meyer, A.

    2015-12-14

    Neutron Spectroscopy employing extreme-conditions sample environments is nowadays a crucial tool for the understanding of fundamental scientific questions as well as for the investigation of materials and chemical-physical properties. For all these kinds of studies, an increased neutron flux over a small sample area is needed. The prototype of a focusing neutron guide component, developed and produced completely at the neutron source FRM II in Garching (Germany), has been installed at the time-of-flight (TOF) disc-chopper neutron spectrometer TOFTOF and came into routine-operation. The design is based on the compressed Archimedes' mirror concept for finite-size divergent sources. It represents a unique device combining the supermirror technology with Adaptive Optics, suitable for broad-bandwidth thermal-cold TOF neutron spectroscopy (here optimized for 1.4–10 Å). It is able to squeeze the beam cross section down to a square centimeter, with a more than doubled signal-to-background ratio, increased efficiency at high scattering angles, and improved symmetry of the elastic resolution function. We present a comparison between the simulated and measured beam cross sections, as well as the performance of the instrument within real experiments. This work intends to show the unprecedented opportunities achievable at already existing instruments, along with useful guidelines for the design and construction of next-generation neutron spectrometers.

  16. Eugene Wigner and Fundamental Symmetry Principles

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

    Eugene Wigner and Fundamental Symmetry Principles Patents * Resources with Additional Information * Wigner Honored "[Eugene P.] Wigner's great contribution to science, for which he won the Nobel Prize in Physics in 1963, was his insight into the fundamental mathematics and physics of quantum mechanics. He applied and extended the mathematical theory of groups to the quantum world of the atom; specifically, he used group theory to organize the quantum energy levels of electrons in atoms in a

  17. Physics

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

    opportunities with AIRIS beams Kathrin Wimmer Central Michigan University and NSCL - Michigan State University May 15 2014 Kathrin Wimmer ATLAS User Workshop AIRIS rates rate [pps] 4 10 5 10 6 10 7 10 neutron number N 0 5 10 15 20 25 30 35 40 proton number Z 0 5 10 15 20 25 30 rate [pps] 4 10 5 10 6 10 7 10 Kathrin Wimmer ATLAS User Workshop intense beams one or two nucleons away from stability significant increase in intensity compared to present status heavier beams available radioactive beams

  18. Neutrons provide new insights into human cell behavior

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

    Neutrons provide new insights into human cell behavior Community Connections: Your link to ... All Issues submit Neutrons provide new insights into human cell behavior Physics and ...

  19. Neutrons provide new insights into human cell behavior

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

    Neutrons provide new insights into human cell behavior Alumni Link: Opportunities, News ... All Issues submit Neutrons provide new insights into human cell behavior Physics and ...

  20. High Dose Neutron Irradiation of Hi-Nicalon Type S Silicon Carbide Composites, Part 2. Mechanical and Physical Properties

    SciTech Connect (OSTI)

    Katoh, Yutai; Nozawa, Takashi; Shih, Chunghao Phillip; Ozawa, Kazumi; Koyanagi, Takaaki; Porter, Wallace D; Snead, Lance Lewis

    2015-01-07

    Nuclear-grade silicon carbide (SiC) composite material was examined for mechanical and thermophysical properties following high-dose neutron irradiation in the High Flux Isotope Reactor at a temperature range of 573–1073 K. Likewise, the material was chemical vapor-infiltrated SiC-matrix composite with a two-dimensional satin weave Hi-Nicalon Type S SiC fiber reinforcement and a multilayered pyrocarbon/SiC interphase. Moderate (1073 K) to very severe (573 K) degradation in mechanical properties was found after irradiation to >70 dpa, whereas no evidence was found for progressive evolution in swelling and thermal conductivity. The swelling was found to recover upon annealing beyond the irradiation temperature, indicating the irradiation temperature, but only to a limited extent. Moreover, the observed strength degradation is attributed primarily to fiber damage for all irradiation temperatures, particularly a combination of severe fiber degradation and likely interphase damage at relatively low irradiation temperatures.

  1. Reactor physics methods, models, and applications used to support the conceptual design of the Advanced Neutron Source

    SciTech Connect (OSTI)

    Gehin, J.C.; Worley, B.A.; Renier, J.P.; Wemple, C.A.; Jahshan, S.N.; Ryskammp, J.M.

    1995-08-01

    This report summarizes the neutronics analysis performed during 1991 and 1992 in support of characterization of the conceptual design of the Advanced Neutron Source (ANS). The methods used in the analysis, parametric studies, and key results supporting the design and safety evaluations of the conceptual design are presented. The analysis approach used during the conceptual design phase followed the same approach used in early ANS evaluations: (1) a strong reliance on Monte Carlo theory for beginning-of-cycle reactor performance calculations and (2) a reliance on few-group diffusion theory for reactor fuel cycle analysis and for evaluation of reactor performance at specific time steps over the fuel cycle. The Monte Carlo analysis was carried out using the MCNP continuous-energy code, and the few- group diffusion theory calculations were performed using the VENTURE and PDQ code systems. The MCNP code was used primarily for its capability to model the reflector components in realistic geometries as well as the inherent circumvention of cross-section processing requirements and use of energy-collapsed cross sections. The MCNP code was used for evaluations of reflector component reactivity effects and of heat loads in these components. The code was also used as a benchmark comparison against the diffusion-theory estimates of key reactor parameters such as region fluxes, control rod worths, reactivity coefficients, and material worths. The VENTURE and PDQ codes were used to provide independent evaluations of burnup effects, power distributions, and small perturbation worths. The performance and safety calculations performed over the subject time period are summarized, and key results are provided. The key results include flux and power distributions over the fuel cycle, silicon production rates, fuel burnup rates, component reactivities, control rod worths, component heat loads, shutdown reactivity margins, reactivity coefficients, and isotope production rates.

  2. 2010 American Conference on Neutron Scattering (ACNS 2010)

    SciTech Connect (OSTI)

    Billinge, Simon

    2011-06-17

    The ACNS provides a focal point for the national neutron user community to strengthen ties within this diverse group, while at the same time promoting neutron research among colleagues in related disciplines identified as “would-be” neutron users. The American Conference on Neutron Scattering thus serves a dual role as a national user meeting and a scientific meeting. As a venue for scientific exchange, the ACNS showcases recent results and provides forums for scientific discussion of neutron research in diverse fields such as hard and soft condensed matter, liquids, biology, magnetism, engineering materials, chemical spectroscopy, crystal structure, and elementary excitations, fundamental physics and development of neutron instrumentation through a combination of invited talks, contributed talks and poster sessions. As a “super-user” meeting, the ACNS fulfills the main objectives of users' meetings previously held periodically at individual national neutron facilities, with the advantage of a larger and more diverse audience. To this end, each of the major national neutron facilities (NIST, LANSCE, HFIR and SNS) have an opportunity to exchange information and update users, and potential users, of their facility. This is also an appropriate forum for users to raise issues that relate to the facilities. For many of the national facilities, this super-user meeting should obviate the need for separate user meetings that tax the time, energy and budgets of facility staff and the users alike, at least in years when the ACNS is held. We rely upon strong participation from the national facilities. The NSSA intends that the American Conference on Neutron Scattering (ACNS) will occur approximately every two years, but not in years that coincide with the International or European Conferences on Neutron Scattering. The ACNS is to be held in association with one of the national neutron centers in a rotating sequence, with the host facility providing local organization

  3. Neutronic reactor

    DOE Patents [OSTI]

    Wende, Charles W. J.; Babcock, Dale F.; Menegus, Robert L.

    1983-01-01

    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.

  4. Plasma Physics

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

    4 Plasma Physics By leveraging plasma under extreme conditions, we concentrate on solving critical scientific challenges such as detecting smuggled nuclear materials, advancing weapons physics and generating fusion energy. Contact Us Group Leader Ray Leeper Email Deputy Group Leader Julie Canepa Email Group Office (505) 665-9145 Laser-generated neutrons Researchers at Los Alamos have successfully demonstrated for the first time that laser-generated neutrons can be enlisted as a useful tool in

  5. High Dose Neutron Irradiation of Hi-Nicalon Type S Silicon Carbide Composites, Part 2. Mechanical and Physical Properties

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

    Katoh, Yutai; Nozawa, Takashi; Shih, Chunghao Phillip; Ozawa, Kazumi; Koyanagi, Takaaki; Porter, Wallace D; Snead, Lance Lewis

    2015-01-07

    Nuclear-grade silicon carbide (SiC) composite material was examined for mechanical and thermophysical properties following high-dose neutron irradiation in the High Flux Isotope Reactor at a temperature range of 573–1073 K. Likewise, the material was chemical vapor-infiltrated SiC-matrix composite with a two-dimensional satin weave Hi-Nicalon Type S SiC fiber reinforcement and a multilayered pyrocarbon/SiC interphase. Moderate (1073 K) to very severe (573 K) degradation in mechanical properties was found after irradiation to >70 dpa, whereas no evidence was found for progressive evolution in swelling and thermal conductivity. The swelling was found to recover upon annealing beyond the irradiation temperature, indicating themore » irradiation temperature, but only to a limited extent. Moreover, the observed strength degradation is attributed primarily to fiber damage for all irradiation temperatures, particularly a combination of severe fiber degradation and likely interphase damage at relatively low irradiation temperatures.« less

  6. EWONAP Procurement Fundamentals

    Broader source: Energy.gov [DOE]

    HUD's Eastern Woodlands Office of Native American Programs in collaboration with the Seminole Tribe of Florida Native Learning Center invites you to attend the Procurement Fundamentals training instructed by Vince Franco, Compliance & Resource Development Director of the Native Learning Center in Atlanta, Georgia on September 8-9, 2014.

  7. HCCI/SCCI Fundamentals

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

    HCCI/SCCI Fundamentals - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced

  8. DOE fundamentals handbook: Material science. Volume 2

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    This handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of the structure and properties of metals. This volume contains the following modules: thermal shock (thermal stress, pressurized thermal shock), brittle fracture (mechanism, minimum pressurization-temperature curves, heatup/cooldown rate limits), and plant materials (properties considered when selecting materials, fuel materials, cladding and reflectors, control materials, nuclear reactor core problems, plant material problems, atomic displacement due to irradiation, thermal and displacement spikes due to irradiation, neutron capture effect, radiation effects in organic compounds, reactor use of aluminum).

  9. Fundamental base closure environmental principles

    SciTech Connect (OSTI)

    Yim, R.A.

    1994-12-31

    Military base closures present a paradox. The rate, scale and timing of military base closures is historically unique. However, each base itself typically does not present unique problems. Thus, the challenge is to design innovative solutions to base redevelopment and remediation issues, while simultaneously adopting common, streamlined or pre-approved strategies to shared problems. The author presents six environmental principles that are fundamental to base closure. They are: remediation not clean up; remediation will impact reuse; reuse will impact remediation; remediation and reuse must be coordinated; environmental contamination must be evaluated as any other initial physical constraint on development, not as an overlay after plans are created; and remediation will impact development, financing and marketability.

  10. Fundamental experiments in velocimetry

    SciTech Connect (OSTI)

    Briggs, Matthew Ellsworth; Hull, Larry; Shinas, Michael

    2009-01-01

    One can understand what velocimetry does and does not measure by understanding a few fundamental experiments. Photon Doppler Velocimetry (PDV) is an interferometer that will produce fringe shifts when the length of one of the legs changes, so we might expect the fringes to change whenever the distance from the probe to the target changes. However, by making PDV measurements of tilted moving surfaces, we have shown that fringe shifts from diffuse surfaces are actually measured only from the changes caused by the component of velocity along the beam. This is an important simplification in the interpretation of PDV results, arising because surface roughness randomizes the scattered phases.

  11. DOE fundamentals handbook: Chemistry

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Chemistry Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of chemistry. The handbook includes information on the atomic structure of matter; chemical bonding; chemical equations; chemical interactions involved with corrosion processes; water chemistry control, including the principles of water treatment; the hazards of chemicals and gases, and basic gaseous diffusion processes. This information will provide personnel with a foundation for understanding the chemical properties of materials and the way these properties can impose limitations on the operation of equipment and systems.

  12. DOE fundamentals handbook: Chemistry

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    This handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of chemistry. This volume contains the following modules: reactor water chemistry (effects of radiation on water chemistry, chemistry parameters), principles of water treatment (purpose; treatment processes [ion exchange]; dissolved gases, suspended solids, and pH control; water purity), and hazards of chemicals and gases (corrosives [acids, alkalies], toxic compounds, compressed gases, flammable/combustible liquids).

  13. Neutron Science and Technology

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

    3 Neutron Science and Technology From a mountaintop in Mexico where we investigate gamma rays, to underground laboratories where we study the behavior of plutonium under extreme conditions, our research spans the spectrum from fundamental to applied. Contact Us Group Leader Frank Merrill Email Deputy Group Leader David Oro Email Deputy Group Leader Keith Rielage Email Group Office Email Inner workings of a wristwatch that was imaged by a new proton microscope At right, a wristwatch was one of

  14. Carl A. Gagliardi PHYSICS

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

    A. Gagliardi PHYSICS Fundamental interactions and nuclear astrophysics - Fellow, American Physical Society - Distinguished Achievement Award in Teaching, AFS, - Texas A&M John C. Hardy PHYSICS Fundamental interactions and exotic nuclei - Fellow, Royal Society of Canada - Fellow, American Physical Society Che Ming Ko PHYSICS Theoretical hadron physics and heavy-ion collisions - Humboldt Research Award - Fellow, American Physical Society Joseph B. Natowitz CHEMISTRY Heavy-ion reaction

  15. Defense, basic, and industrial research at the Los Alamos Neutron Science Center: Proceedings

    SciTech Connect (OSTI)

    Longshore, A.; Salgado, K.

    1995-10-01

    The Workshop on Defense, Basic, and Industrial Research at the Los Alamos Neutron Science Center gathered scientists from Department of Energy national laboratories, other federal institutions, universities, and industry to discuss the use of neutrons in science-based stockpile stewardship, The workshop began with presentations by government officials, senior representatives from the three weapons laboratories, and scientific opinion leaders. Workshop participants then met in breakout sessions on the following topics: materials science and engineering; polymers, complex fluids, and biomaterials; fundamental neutron physics; applied nuclear physics; condensed matter physics and chemistry; and nuclear weapons research. They concluded that neutrons can play an essential role in science-based stockpile stewardship and that there is overlap and synergy between defense and other uses of neutrons in basic, applied, and industrial research from which defense and civilian research can benefit. This proceedings is a collection of talks and papers from the plenary, technical, and breakout session presentations. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  16. CVD diamond - fundamental phenomena

    SciTech Connect (OSTI)

    Yarbrough, W.A.

    1993-01-01

    This compilation of figures and diagrams addresses the basic physical processes involved in the chemical vapor deposition of diamond. Different methods of deposition are illustrated. For each method, observations are made of the prominent advantages and disadvantages of the technique. Chemical mechanisms of nucleation are introduced.

  17. Neutron guide

    DOE Patents [OSTI]

    Greene, Geoffrey L.

    1999-01-01

    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.

  18. Neutron dosimetry

    DOE Patents [OSTI]

    Quinby, Thomas C.

    1976-07-27

    A method of measuring neutron radiation within a nuclear reactor is provided. A sintered oxide wire is disposed within the reactor and exposed to neutron radiation. The induced radioactivity is measured to provide an indication of the neutron energy and flux within the reactor.

  19. (Neutron scattering studies of the high-temperature superconducting materials)

    SciTech Connect (OSTI)

    Mook, H.A. Jr.

    1991-01-04

    The traveler was given beam time at the ILL to continue neutron scattering work on high-temperature superconductivity. The unique facilities at the ILL for both high-energy and low-energy neutron instrumentation made the experiments possible. The measurements consisted of two basic types. The first of these is the study of the nature of spin fluctuations in high-{Tc} materials. This work is fundamental to the mechanism that is responsible for the high-transition temperatures. The second consisted of experiments on the flux lattice in high-temperature superconductors. The flux lattice has interesting physics in its own right and is important in understanding the current-carrying capability of superconductors.

  20. Neutron Electric Dipole Moments from Beyond the Standard Model...

    Office of Scientific and Technical Information (OSTI)

    Beyond the Standard Model Physics Citation Details In-Document Search Title: Neutron Electric Dipole Moments from Beyond the Standard Model Physics Authors: Bhattacharya, Tanmoy ...

  1. Neutron Electric Dipole Moments from Beyond the Standard Model...

    Office of Scientific and Technical Information (OSTI)

    Beyond the Standard Model Physics Citation Details In-Document Search Title: Neutron Electric Dipole Moments from Beyond the Standard Model Physics You are accessing a ...

  2. MANTA. An Integral Reactor Physics Experiment to Infer the Neutron Capture Cross Sections of Actinides and Fission Products in Fast and Epithermal Spectra

    SciTech Connect (OSTI)

    Youinou, Gilles Jean-Michel

    2015-10-01

    Neutron cross-sections characterize the way neutrons interact with matter. They are essential to most nuclear engineering projects and, even though theoretical progress has been made as far as the predictability of neutron cross-section models, measurements are still indispensable to meet tight design requirements for reduced uncertainties. Within the field of fission reactor technology, one can identify the following specializations that rely on the availability of accurate neutron cross-sections: (1) fission reactor design, (2) nuclear fuel cycles, (3) nuclear safety, (4) nuclear safeguards, (5) reactor monitoring and neutron fluence determination and (6) waste disposal and transmutation. In particular, the assessment of advanced fuel cycles requires an extensive knowledge of transuranics cross sections. Plutonium isotopes, but also americium, curium and up to californium isotope data are required with a small uncertainty in order to optimize significant features of the fuel cycle that have an impact on feasibility studies (e.g. neutron doses at fuel fabrication, decay heat in a repository, etc.). Different techniques are available to determine neutron cross sections experimentally, with the common denominator that a source of neutrons is necessary. It can either come from an accelerator that produces neutrons as a result of interactions between charged particles and a target, or it can come from a nuclear reactor. When the measurements are performed with an accelerator, they are referred to as differential since the analysis of the data provides the cross-sections for different discrete energies, i.e. σ(Ei), and for the diffusion cross sections for different discrete angles. Another approach is to irradiate a very pure sample in a test reactor such as the Advanced Test Reactor (ATR) at INL and, after a given time, determine the amount of the different transmutation products. The precise characterization of the nuclide densities before and after

  3. Fundamentals of plasma simulation

    SciTech Connect (OSTI)

    Forslund, D.W.

    1985-01-01

    With the increasing size and speed of modern computers, the incredibly complex nonlinear properties of plasmas in the laboratory and in space are being successfully explored in increasing depth. Of particular importance have been numerical simulation techniques involving finite size particles on a discrete mesh. After discussing the importance of this means of understanding a variety of nonlinear plasma phenomena, we describe the basic elements of particle-in-cell simulation and their limitations and advantages. The differencing techniques, stability and accuracy issues, data management and optimization issues are discussed by means of a simple example of a particle-in-cell code. Recent advances in simulation methods allowing large space and time scales to be treated with minimal sacrifice in physics are reviewed. Various examples of nonlinear processes successfully studied by plasma simulation will be given.

  4. DOE fundamentals handbook: Material science. Volume 1

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    This handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of the structure and properties of metals. This volume contains the two modules: structure of metals (bonding, common lattic types, grain structure/boundary, polymorphis, alloys, imperfections in metals) and properties of metals (stress, strain, Young modulus, stress-strain relation, physical properties, working of metals, corrosion, hydrogen embrittlement, tritium/material compatibility).

  5. The advanced neutron source research and development plan

    SciTech Connect (OSTI)

    Selby, D.L.

    1995-08-01

    The Advanced Neutron Source (ANS) is being designed as a user-oriented neutron research laboratory centered around the most intense continuous beams of thermal and subthermal neutrons in the world (an order of magnitude more intense than beams available from the most advanced existing reactors). The ANS will be built around a new research reactor of 330-MW fission power, producing an unprecedented peak thermal flux of >7 {center_dot} 10{sup 19} {center_dot} m{sup -2} {center_dot} s{sup -1}. Primarily a research facility, the ANS will accommodate more than 1000 academic, industrial, and government researchers each year. They will conduct basic research in all branches of science as well as applied research leading to better understanding of new materials, including high temperature super conductors, plastics, and thin films. Some 48 neutron beam stations will be set up in the ANS beam rooms and the neutron guide hall for neutron scattering and for fundamental and nuclear physics research. There also will be extensive facilities for materials irradiation, isotope production, and analytical chemistry. The top level work breakdown structure (WBS) for the project. As noted in this figure, one component of the project is a research and development (R&D) program (WBS 1.1). This program interfaces with all of the other project level two WBS activities. Because one of the project guidelines is to meet minimum performance goals without relying on new inventions, this R&D activity is not intended to produce new concepts to allow the project to meet minimum performance goals. Instead, the R&D program will focus on the four objectives described.

  6. The Advanced Neutron Source research and development plan

    SciTech Connect (OSTI)

    Selby, D.L.

    1992-11-30

    The Advanced Neutron Source (ANS) is being designed as a user-oriented neutron research laboratory centered around the most intense continuous beams of thermal and subthermal neutrons in the world. The ANS will be built around a new research reactor of {approximately} 330 MW fission power, producing an unprecedented peak thermal flux of > 7 {times} 10{sup 19} M{sup {minus}2} {center_dot} S{sup {minus}1}. Primarily a research facility, the ANS will accommodate more than 1000 academic, industrial, and government researchers each year. They will conduct basic research in all branches of science-as well as applied research-leading to better understanding of new materials, including high temperature super conductors, plastics, and thin films. Some 48 neutron beam stations will be set up in the ANS beam rooms and the neutron guide hall for neutron scattering and for fundamental and nuclear physics research. There also will be extensive facilities for materials irradiation, isotope production, and analytical chemistry. The R&D program will focus on the four objectives: Address feasibility issues; provide analysis support; evaluate options for improvement in performance beyond minimum requirements; and provide prototype demonstrations for unique facilities. The remainder of this report presents (1) the process by which the R&D activities are controlled and (2) a discussion of the individual tasks that have been identified for the R&D program, including their justification, schedule and costs. The activities discussed in this report will be performed by Martin Marietta Energy Systems, Inc. (MMES) through the Oak Ridge National Laboratory (ORNL) and through subcontracts with industry, universities, and other national laboratories. It should be noted that in general a success path has been assumed for all tasks.

  7. The Advanced Neutron Source research and development plan

    SciTech Connect (OSTI)

    Selby, D.L.

    1992-11-30

    The Advanced Neutron Source (ANS) is being designed as a user-oriented neutron research laboratory centered around the most intense continuous beams of thermal and subthermal neutrons in the world. The ANS will be built around a new research reactor of [approximately] 330 MW fission power, producing an unprecedented peak thermal flux of > 7 [times] 10[sup 19] M[sup [minus]2] [center dot] S[sup [minus]1]. Primarily a research facility, the ANS will accommodate more than 1000 academic, industrial, and government researchers each year. They will conduct basic research in all branches of science-as well as applied research-leading to better understanding of new materials, including high temperature super conductors, plastics, and thin films. Some 48 neutron beam stations will be set up in the ANS beam rooms and the neutron guide hall for neutron scattering and for fundamental and nuclear physics research. There also will be extensive facilities for materials irradiation, isotope production, and analytical chemistry. The R D program will focus on the four objectives: Address feasibility issues; provide analysis support; evaluate options for improvement in performance beyond minimum requirements; and provide prototype demonstrations for unique facilities. The remainder of this report presents (1) the process by which the R D activities are controlled and (2) a discussion of the individual tasks that have been identified for the R D program, including their justification, schedule and costs. The activities discussed in this report will be performed by Martin Marietta Energy Systems, Inc. (MMES) through the Oak Ridge National Laboratory (ORNL) and through subcontracts with industry, universities, and other national laboratories. It should be noted that in general a success path has been assumed for all tasks.

  8. Neutron Scattering Studies of Vortex Matter in Type-II Superconductors

    SciTech Connect (OSTI)

    Xinsheng Ling

    2012-02-02

    The proposed program is an experimental study of the fundamental properties of Abrikosov vortex matter in type-II superconductors. Most superconducting materials used in applications such as MRI are type II and their transport properties are determined by the interplay between random pinning, interaction and thermal fluctuation effects in the vortex state. Given the technological importance of these materials, a fundamental understanding of the vortex matter is necessary. The vortex lines in type-II superconductors also form a useful model system for fundamental studies of a number of important issues in condensed matter physics, such as the presence of a symmetry-breaking phase transition in the presence of random pinning. Recent advances in neutron scattering facilities such as the major upgrade of the NIST cold source and the Spallation Neutron Source are providing unprecedented opportunities in addressing some of the longstanding issues in vortex physics. The core component of the proposed program is to use small angle neutron scattering and Bitter decoration experiments to provide the most stringent test of the Bragg glass theory by measuring the structure factor in both the real and reciprocal spaces. The proposed experiments include a neutron reflectometry experiment to measure the precise Q-dependence of the structure factor of the vortex lattice in the Bragg glass state. A second set of SANS experiments will be on a shear-strained Nb single crystal for testing a recently proposed theory of the stability of Bragg glass. The objective is to artificially create a set of parallel grain boundaries into a Nb single crystal and use SANS to measure the vortex matter diffraction pattern as a function of the changing angle between the applied magnetic field to the grain boundaries. The intrinsic merits of the proposed work are a new fundamental understanding of type-II superconductors on which superconducting technology is based, and a firm understanding of phases

  9. Spallation Neutron Source reaches megawatt power

    SciTech Connect (OSTI)

    Dr. William F. Brinkman

    2009-09-30

    The Department of Energy's Spallation Neutron Source (SNS), already the world's most powerful facility for pulsed neutron scattering science, is now the first pulsed spallation neutron source to break the one-megawatt barrier. "Advances in the materials sciences are fundamental to the development of clean and sustainable energy technologies. In reaching this milestone of operating power, the Spallation Neutron Source is providing scientists with an unmatched resource for unlocking the secrets of materials at the molecular level," said Dr. William F. Brinkman, Director of DOE's Office of Science.

  10. Spallation Neutron Source reaches megawatt power

    ScienceCinema (OSTI)

    Dr. William F. Brinkman

    2010-01-08

    The Department of Energy's Spallation Neutron Source (SNS), already the world's most powerful facility for pulsed neutron scattering science, is now the first pulsed spallation neutron source to break the one-megawatt barrier. "Advances in the materials sciences are fundamental to the development of clean and sustainable energy technologies. In reaching this milestone of operating power, the Spallation Neutron Source is providing scientists with an unmatched resource for unlocking the secrets of materials at the molecular level," said Dr. William F. Brinkman, Director of DOE's Office of Science.

  11. Ultracold neutrons

    SciTech Connect (OSTI)

    Saunders, Alexander

    2015-06-22

    This series of slides describes ultracold neutrons (UCN) and their properties, various UCN sources, and an overview of UCN-based experiments. Numerous diagrams and photographs are included.

  12. Review of Non-Neutron and Neutron Nuclear Data, 2004

    SciTech Connect (OSTI)

    Holden, Norman E.

    2005-05-24

    Review articles are in preparation for the 2004 edition of the CRC Handbook of Chemistry and Physics dealing with the evaluation of both non-neutron and neutron nuclear data. Data on the discovery of element 110, Darmstadtium, and element 111 have been officially accepted, while data on element 118 have been withdrawn. Data to be presented include revised values for very short-lived nuclides, long-lived nuclides, and beta-beta decay measurements. There has been a reassessment of the spontaneous fission (sf) half-lives, which distinguishes between sf decay half-lives and cluster decay half-lives, and with cluster-fission decay. New measurements of isotopic abundance values for many elements will be discussed with an emphasis on the minor isotopes of interest for use in neutron activation analysis measurements. Neutron resonance integrals will be discussed emphasizing the differences between the calculated values obtained from the analytical integration over neutron resonances and the measured values in a neutron reactor-spectrum, which does not quite conform to the assumed 1/E neutron energy spectrum. The method used to determine the neutron resonance integral from measurement, using neutron activation analysis, will be discussed.

  13. REVIEW OF NON-NEUTRON AND NEUTRON NUCLEAR DATA, 2004.

    SciTech Connect (OSTI)

    HOLDEN, N.E.

    2004-09-26

    Review articles are in preparation for the 2004 edition of the CRC Handbook of Chemistry and Physics dealing with the evaluation of both non-neutron and neutron nuclear data. Data on the discovery of element 110, Darmstadtium, and element 111 have been officially accepted, while data on element 11 8 have been withdrawn. Data to be presented include revised values for very short-lived nuclides, long-lived nuclides and beta-beta decay measurements. There has been a reassessment of the spontaneous fission (sf) half-lives, which distinguishes between sf decay half-lives and cluster decay half-lives and with cluster-fission decay. New measurements of isotopic abundance values for many elements will be discussed with an emphasis on the minor isotopes of interest for use in neutron activation analysis measurements. Neutron resonance integrals will be discussed emphasizing the differences between the calculated values obtained from the analytical integration over neutron resonances and the measured values in a neutron reactor-spectrum, which does not quite conform to the assumed 1/E neutron energy spectrum. The method used to determine the neutron resonance integral from measurement, using neutron activation analysis, will be discussed.

  14. MAGNETIC NEUTRON SCATTERING

    SciTech Connect (OSTI)

    ZALIZNYAK,I.A.; LEE,S.H.

    2004-07-30

    Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern science

  15. Theoretical Physics

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

    HEP Theoretical Physics Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664 Email Bruce Carlsten (505) 667-5657 Email HEP Theory at Los Alamos The Theoretical High Energy Physics group at Los Alamos National Laboratory is active in a number of diverse areas of research. Their primary areas of interest are in physics beyond the Standard Model, cosmology, dark matter, lattice quantum chromodynamics, neutrinos, the fundamentals of

  16. Handbook of heat transfer fundamentals

    SciTech Connect (OSTI)

    Rohsenow, W.M.; Hartnett, J.P.; Ganic, E.N.

    1985-01-01

    This handbook is on the fundamentals of heat transfer. It provides coverage on conduction, convection, and radiation and on thermophysical properties of materials.

  17. Quantum states of neutrons in the gravitational and centrifugal potentials in a new GRANIT spectrometer

    ScienceCinema (OSTI)

    None

    2011-10-06

    We will discuss the scientific program to be studied in a new gravitational spectrometer GRANIT in a broad context of quantum states (quantum behaviour) of ultracold neutrons (UCN) in gravitational [1] and centrifugal [2] potentials, as well as applications of these phenomena/spectrometer to various domains of physics, ranging from studies of fundamental short-range interactions and symmetries to neutron quantum optics and reflectometry using UCN. All these topics, as well as related instrumental and methodical developments have been discussed during dedicated GRANIT-2010 Workshop [3]. The GRANIT spectrometer has been recently installed at the Institut Laue-Langevin, Grenoble, France [4] and could become operational in near future. 1. V.V. Nesvizhevsky et al (2002), Nature 415, 297. 2. V.V. Nesvizhevsky et al (2010), Nature Physics 6, 114. 3. GRANIT-2010, Les Houches, 14-19 february 2010. 4. M. Kreuz et al (2009), NIM 611, 326.

  18. Interfacial Magnetism in Complex Oxide Heterostructures Probed by Neutrons and X-rays

    SciTech Connect (OSTI)

    Liu, Yaohua; Ke, Xianglin

    2015-09-02

    Magnetic complex-oxide heterostructures are of keen interest because a wealth of phenomena at the interface of dissimilar materials can give rise to fundamentally new physics and potentially valuable functionalities. Altered magnetization, novel magnetic coupling and emergent interfacial magnetism at the epitaxial layered-oxide interfaces have all been intensively investigated, which shapes our understanding on how to utilize those materials, particularly for spintronics. Neutron and x-ray based techniques have played a decisive role in characterizing interfacial magnetic structures and clarifying the underlying physics in this rapidly developing field. Here we review some recent experimental results, with an emphasis on those studied via polarized neutron reflectometery and polarized x-ray absorption spectroscopy. We conclude with some perspectives.

  19. Interfacial Magnetism in Complex Oxide Heterostructures Probed by Neutrons and X-rays

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

    Liu, Yaohua; Ke, Xianglin

    2015-09-02

    Magnetic complex-oxide heterostructures are of keen interest because a wealth of phenomena at the interface of dissimilar materials can give rise to fundamentally new physics and potentially valuable functionalities. Altered magnetization, novel magnetic coupling and emergent interfacial magnetism at the epitaxial layered-oxide interfaces have all been intensively investigated, which shapes our understanding on how to utilize those materials, particularly for spintronics. Neutron and x-ray based techniques have played a decisive role in characterizing interfacial magnetic structures and clarifying the underlying physics in this rapidly developing field. Here we review some recent experimental results, with an emphasis on those studied viamore » polarized neutron reflectometery and polarized x-ray absorption spectroscopy. We conclude with some perspectives.« less

  20. Neutronic reactor

    DOE Patents [OSTI]

    Wende, Charles W. J.

    1976-08-17

    A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.

  1. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Fermi, E.; Zinn, W.H.; Anderson, H.L.

    1958-09-16

    Means are presenied for increasing the reproduction ratio of a gaphite- moderated neutronic reactor by diminishing the neutron loss due to absorption or capture by gaseous impurities within the reactor. This means comprised of a fluid-tight casing or envelope completely enclosing the reactor and provided with a valve through which the casing, and thereby the reactor, may be evacuated of atmospheric air.

  2. Neutron tubes

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Lou, Tak Pui; Reijonen, Jani

    2008-03-11

    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.

  3. Neutron source

    DOE Patents [OSTI]

    Cason, J.L. Jr.; Shaw, C.B.

    1975-10-21

    A neutron source which is particularly useful for neutron radiography consists of a vessel containing a moderating media of relatively low moderating ratio, a flux trap including a moderating media of relatively high moderating ratio at the center of the vessel, a shell of depleted uranium dioxide surrounding the moderating media of relatively high moderating ratio, a plurality of guide tubes each containing a movable source of neutrons surrounding the flux trap, a neutron shield surrounding one part of each guide tube, and at least one collimator extending from the flux trap to the exterior of the neutron source. The shell of depleted uranium dioxide has a window provided with depleted uranium dioxide shutters for each collimator. Reflectors are provided above and below the flux trap and on the guide tubes away from the flux trap.

  4. Hybrid superconducting neutron detectors

    SciTech Connect (OSTI)

    Merlo, V.; Lucci, M.; Ottaviani, I.; Salvato, M.; Cirillo, M.; Scherillo, A.; Celentano, G.; Pietropaolo, A.

    2015-03-16

    A neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction, {sup 10}B + n → α + {sup 7}Li, with α and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T = 8 K and current-biased below the critical current I{sub c}, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40 mV are measured while the bias current can be properly modulated to bring the strip back to the superconducting state, thus resetting the detector. Measurements on the counting rate of the device are presented and the basic physical features of the detector are discussed.

  5. DOE Science Showcase - Neutron Science Research from DOE Databases | OSTI,

    Office of Scientific and Technical Information (OSTI)

    US Dept of Energy Office of Scientific and Technical Information Neutron Science Research from DOE Databases Additional neutron science research in DOE Databases Information Bridge Neutron scattering research was pioneered in 1946 by ORNL's Clifford G. Shull, winner of 1994 Nobel Prize in Physics. Access Shull's early research records in Energy Citations Database. Neutron scattering research was pioneered in 1946 by ORNL's Clifford G. Shull, winner of 1994 Nobel Prize in Physics. Access

  6. Fundamentals of gas measurement II

    SciTech Connect (OSTI)

    Smith, J.P.

    1995-12-01

    A knowledge of the Fundamentals of Gas Measurement is essential for all technicians and engineers that are called upon to perform gas volume calculations. These same people must have at least a working knowledge of the fundamentals to perform their everyday jobs including equipment calibrations, specific gravity tests, collecting gas samples, etc. To understand the fundamentals, one must be familiar with the definitions of the terms that are used in day-to- day gas measurement operations. They also must know how to convert some values from one quantity as measured to another quantity that is called for in the gas purchase or sales contracts or transportation agreements.

  7. Thermal neutron detection system

    DOE Patents [OSTI]

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

    2000-01-01

    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.

  8. Sandia Energy - HCCI/SCCI Engine Fundamentals

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

    HCCISCCI Engine Fundamentals Home Transportation Energy Predictive Simulation of Engines Engine Combustion Automotive HCCISCCI Engine Fundamentals HCCISCCI Engine...

  9. Sandia Energy - HCCI/SCCI Engine Fundamentals

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

    HCCISCCI Engine Fundamentals Home Transportation Energy Predictive Simulation of Engines Engine Combustion Heavy Duty HCCISCCI Engine Fundamentals HCCISCCI Engine...

  10. Tribal Energy NEPA Fundamentals Workshop

    Broader source: Energy.gov [DOE]

    The Tribal Energy NEPA Fundamentals Workshop is a three-day workshop for tribes to understand how to manage the National Environmental Policy Act (NEPA) process and implement the Council on...

  11. NEUTRONIC REACTORS

    DOE Patents [OSTI]

    Wigner, E.P.

    1960-11-22

    A nuclear reactor is described wherein horizontal rods of thermal- neutron-fissionable material are disposed in a body of heavy water and extend through and are supported by spaced parallel walls of graphite.

  12. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Wade, E.J.

    1958-09-16

    This patent relates to a reflector means for a neutronic reactor. A reflector comprised of a plurality of vertically movable beryllium control members is provided surrounding the sides of the reactor core. An absorber of fast neutrons comprised of natural uramum surrounds the reflector. An absorber of slow neutrons surrounds the absorber of fast neutrons and is formed of a plurality of beryllium blocks having natural uranium members distributcd therethrough. in addition, a movable body is positioned directly below the core and is comprised of a beryllium reflector and an absorbing member attached to the botiom thereof, the absorbing member containing a substance selected from the goup consisting of natural urantum and Th/sup 232/.

  13. Aerial Neutron Detection: Neutron Signatures for Nonproliferation and Emergency Response Applications

    SciTech Connect (OSTI)

    Maurer, Richard J.; Stampahar, Thomas G.; Smith, Ethan X.; Mukhopadhyay, Sanjoy; Wolff, Ronald S.; Rourke, Timothy J.; LeDonne, Jeffrey P.; Avaro, Emanuele; Butler, D. Andre; Borders, Kevin L.; Stampahar, Jezabel; Schuck, William H.; Selfridge, Thomas L.; McKissack, Thomas M.; Duncan, William W.; Hendricks, Thane J.

    2012-10-17

    From 2007 to the present, the Remote Sensing Laboratory has been conducting a series of studies designed to expand our fundamental understanding of aerial neutron detection with the goal of designing an enhanced sensitivity detection system for long range neutron detection. Over 35 hours of aerial measurements in a helicopter were conducted for a variety of neutron emitters such as neutron point sources, a commercial nuclear power reactor, nuclear reactor spent fuel in dry cask storage, depleted uranium hexafluoride and depleted uranium metal. The goals of the project were to increase the detection sensitivity of our instruments such that a 5.4 × 104 neutron/second source could be detected at 100 feet above ground level at a speed of 70 knots and to enhance the long-range detection sensitivity for larger neutron sources, i.e., detection ranges above 1000 feet. In order to increase the sensitivity of aerial neutron detection instruments, it is important to understand the dynamics of the neutron background as a function of altitude. For aerial neutron detection, studies have shown that the neutron background primarily originates from above the aircraft, being produced in the upper atmosphere by galactic cosmic-ray interactions with air molecules. These interactions produce energetic neutrons and charged particles that cascade to the earth’s surface, producing additional neutrons in secondary collisions. Hence, the neutron background increases as a function of altitude which is an impediment to long-range neutron detection. In order to increase the sensitivity for long range detection, it is necessary to maintain a low neutron background as a function of altitude. Initial investigations show the variation in the neutron background can be decreased with the application of a cosmic-ray shield. The results of the studies along with a representative data set are presented.

  14. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Fraas, A.P.; Mills, C.B.

    1961-11-21

    A neutronic reactor in which neutron moderation is achieved primarily in its reflector is described. The reactor structure consists of a cylindrical central "island" of moderator and a spherical moderating reflector spaced therefrom, thereby providing an annular space. An essentially unmoderated liquid fuel is continuously passed through the annular space and undergoes fission while contained therein. The reactor, because of its small size, is particularly adapted for propulsion uses, including the propulsion of aircraft. (AEC)

  15. NEUTRON SOURCES

    DOE Patents [OSTI]

    Richmond, J.L.; Wells, C.E.

    1963-01-15

    A neutron source is obtained without employing any separate beryllia receptacle, as was formerly required. The new method is safer and faster, and affords a source with both improved yield and symmetry of neutron emission. A Be container is used to hold and react with Pu. This container has a thin isolating layer that does not obstruct the desired Pu--Be reaction and obviates procedures previously employed to disassemble and remove a beryllia receptacle. (AEC)

  16. Neutron range spectrometer

    DOE Patents [OSTI]

    Manglos, S.H.

    1988-03-10

    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.

  17. DOE-HDBK-1018/2-93; DOE Fundamentals Handbook Mechanical Science...

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

    The Department of Energy (DOE) Fundamentals Handbooks consist of ... Science; Chemistry; Engineering Symbology, Prints, and Drawings; and Nuclear Physics and Reactor Theory. ...

  18. DOE-HDBK-1018/1-93; DOE Fundamentals Handbook Mechanical Science...

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

    The Department of Energy (DOE) Fundamentals Handbooks consist of ... Science; Chemistry; Engineering Symbology, Prints, and Drawings; and Nuclear Physics and Reactor Theory. ...

  19. American Conference on Neutron Scattering 2014

    SciTech Connect (OSTI)

    Dillen, J. Ardie

    2014-12-31

    Scientists from the around the world converged in Knoxville, TN to have share ideas, present technical information and contribute to the advancement of neutron scattering. Featuring over 400 oral/poster presentations, ACNS 2014 offered a strong program of plenary, invited and contributed talks and poster sessions covering topics in soft condensed matter, hard condensed matter, biology, chemistry, energy and engineering applications in neutron physics – confirming the great diversity of science that is enabled by neutron scattering.

  20. Neutron physics of the Re/Os clock. I. Measurement of the (n, ) cross sections of 186,187,188Os at the CERN n TOF facility

    SciTech Connect (OSTI)

    Mosconi, M.; Fujii, K.; Mengoni, A.; Domingo-Pardo, C.; Kappeler, F.; Koehler, Paul Edward

    2010-01-01

    The precise determination of the neutron capture cross sections of 186Os and 187Os is important to define the s-process abundance of 187Os at the formation of the solar system. This quantity can be used to evaluate the radiogenic component of the abundance of 187Os due to the decay of the unstable 187Re (t1/2 = 41.2 Gyr) and from this to infer the time duration of the nucleosynthesis in our galaxy (Re/Os cosmochronometer). The neutron capture cross sections of 186Os, 187Os, and 188Os have been measured at the CERN n TOF facility from 1 eV to 1 MeV, covering the entire energy range of astrophysical interest. The measurement has been performed by time-of-flight technique using isotopically enriched samples and two C6D6 scintillation detectors for recording the prompt rays emitted in the capture events. Maxwellian averaged capture cross sections have been determined for thermal energies between kT = 5 and 100 keV corresponding to all possible s-process scenarios. The estimated uncertainties for the values at 30 keV are 4.1, 3.3, and 4.7% for 186Os, 187Os, and 188Os, respectively.

  1. Neutron physics of the Re/Os clock. III. Resonance analyses and stellar (n,gamma) cross sections of {sup 186,187,188}Os

    SciTech Connect (OSTI)

    Fujii, K.; Abbondanno, U.; Belloni, F.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Kaeppeler, F.; Audouin, L.; Dillmann, I.; Heil, M.; Plag, R.; Voss, F.; Walter, S.; Wisshak, K.; Mengoni, A.; Domingo-Pardo, C.; Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.

    2010-07-15

    Neutron resonance analyses have been performed for the capture cross sections of {sup 186}Os, {sup 187}Os, and {sup 188}Os measured at the n{sub T}OF facility at cern. Resonance parameters have been extracted up to 5, 3, and 8 keV, respectively, using the sammy code for a full R-matrix fit of the capture yields. From these results average resonance parameters were derived by a statistical analysis to provide a comprehensive experimental basis for modeling of the stellar neutron capture rates of these isotopes in terms of the Hauser-Feshbach statistical model. Consistent calculations for the capture and inelastic reaction channels are crucial for the evaluation of stellar enhancement factors to correct the Maxwellian averaged cross sections obtained from experimental data for the effect of thermally populated excited states. These factors have been calculated for the full temperature range of current scenarios of s-process nucleosynthesis using the combined information of the experimental data in the region of resolved resonances and in the continuum. The consequences of this analysis for the s-process component of the {sup 187}Os abundance and the related impact on the evaluation of the time duration of galactic nucleosynthesis via the Re/Os cosmochronometer are discussed.

  2. Neutron physics of the Re/Os clock. III. Resonance analyses and stellar (n, ) cross sections of 186,187,188Os

    SciTech Connect (OSTI)

    Fujii, K.; Koehler, Paul Edward

    2010-01-01

    Neutron resonance analyses have been performed for the capture cross sections of 186Os, 187Os, and 188Os measured at the n TOF facility at CERN. Resonance parameters have been extracted up to 5, 3, and 8 keV, respectively, using the SAMMY code for a full R-matrix fit of the capture yields. From these results average resonance parameters were derived by a statistical analysis to provide a comprehensive experimental basis for modeling of the stellar neutron capture rates of these isotopes in terms of the Hauser-Feshbach statistical model. Consistent calculations for the capture and inelastic reaction channels are crucial for the evaluation of stellar enhancement factors to correct the Maxwellian averaged cross sections obtained from experimental data for the effect of thermally populated excited states. These factors have been calculated for the full temperature range of current scenarios of s-process nucleosynthesis using the combined information of the experimental data in the region of resolved resonances and in the continuum. The consequences of this analysis for the s-process component of the 187Os abundance and the related impact on the evaluation of the time duration of galactic nucleosynthesis via the Re/Os cosmochronometer are discussed.

  3. Sensitivity of the electric dipole polarizability to the neutron skin thickness in {sup 208}Pb

    SciTech Connect (OSTI)

    Roca-Maza, X.; Agrawal, B. K.; Colo, G.; Nazarewicz, W.; Paar, N.; Piekarewicz, J.; Reinhard, P.-G.; Vretenar, D.

    2012-10-20

    The static dipole polarizability, {alpha}{sub D}, in {sup 208}Pb has been recently measured with highresolution via proton inelastic scattering at the Research Center for Nuclear Physics (RCNP) [1]. This observable is thought to be intimately connected with the neutron skin thickness, r{sub skin}, of the same nucleus and, more fundamentally, it is believed to be associated with the density dependence of the nuclear symmetry energy. The impact of r{sub skin} on {alpha}{sub D} in {sup 208}Pb is investigated and discussed on the basis of a large and representative set of relativistic and non-relativistic nuclear energy density functionals (EDF) [2].

  4. Fundamental Properties of QCD Matter produced at RHIC and the LHC | Argonne

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

    Leadership Computing Facility image illustrates how protons, neutrons, and other hadrons formed from quarks and gluons during the QCD transition as the universe expanded The image illustrates how protons, neutrons, and other hadrons formed from quarks and gluons during the QCD transition as the universe expanded. Since the transition is a crossover, there is no sharp temperature, only a broad range where the transition happened. Sandor Katz, Eotvos University, Budapest, Hungary Fundamental

  5. Electronically- and crystal-structure-driven magnetic structures and physical properties of RScSb (R = rare earth) compounds. A neutron diffraction, magnetization and heat capacity study

    SciTech Connect (OSTI)

    Ritter, C; Dhar, S K; Kulkarni, R; Provino, A; Paudyal, Durga; Manfrinetti, Pietro; Gschneidner, Karl A

    2014-08-14

    The synthesis of the new equiatomic RScSb ( R = La-Nd, Sm, Gd-Tm, Lu, Y) compounds has been recently reported. These rare earth compounds crystallize in two different crystal structures, adopting the CeScSi-type ( I 4/ mmm) for the lighter R (La-Nd, Sm) and the CeFeSi-type (P4 /nmm) structure for the heavier R ( R = Gd-Tm, Lu, Y). Here we report the results of neutron diffraction, magnetization and heat capacity measurements on some of these compounds ( R = Ce, Pr, Nd, Gd and Tb). Band structure calculations have also been performed on CeScSb and GdScGe (CeScSi-type), and on GdScSb and TbScSb (CeFeSi-type) to compare and understand the exchange interactions in CeScSi and CeFeSi structure types. The neutron diffraction investigation shows that all five compounds order magnetically, with the highest transition temperature of 66 K in TbScSb and the lowest of about 9 K in CeScSb. The magnetic ground state is simple ferromagnetic (τ = [0 0 0]) in CeScSb, as well in NdScSb for 32 >T > 22 K. Below 22 K a second magnetic transition, with propagation vector τ = [¼ ¼ 0], appears in NdScSb. PrScSb has a magnetic structure within, determined by mostly ferromagnetic interactions and antiferromagnetic alignment of the Pr-sites connected through the I-centering ( τ = [1 0 0]). A cycloidal spiral structure with a temperature dependent propagation vector τ = [δ δ ½] is found in TbScSb. The results of magnetization and heat capacity lend support to the main conclusions derived from neutron diffraction. As inferred from a sharp peak in magnetization, GdScSb orders antiferromagnetically at 56 K. First principles calculations show lateral shift of spin split bands towards lower energy from the Fermi level as the CeScSi-type structure changes to the CeFeSi-type structure. This rigid shift may force the system to transform from exchange split ferromagnetic state to the antiferromagnetic state in RScSb compounds (as seen for example in GdScSb and TbScSb) and is proposed to

  6. Neutron Production by Muon Spallation I: Theory (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Title: Neutron Production by Muon Spallation I: Theory We ... OSTI Identifier: 900172 Report Number(s): UCRL-TR-226323 ... Language: English Subject: 72 PHYSICS OF ELEMENTARY ...

  7. Notes on the Lumped Backward Master Equation for the Neutron...

    Office of Scientific and Technical Information (OSTI)

    ... overly restricting the underlying physics (e.g., fission neutron multiplicity, reactivity variation) is clearly essential in developing an understanding of the behavior of ...

  8. Neutron Detectors for Detection of Nuclear Materials at LANL...

    Office of Science (SC) Website

    Neutron Detectors for Detection of Nuclear Materials at LANL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of Nuclear ...

  9. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Hurwitz, H. Jr.; Brooks, H.; Mannal, C.; Payne, J.H.; Luebke, E.A.

    1959-03-24

    A reactor of the heterogeneous, liquid cooled type is described. This reactor is comprised of a central region of a plurality of vertically disposed elongated tubes surrounded by a region of moderator material. The central region is comprised of a central core surrounded by a reflector region which is surrounded by a fast neutron absorber region, which in turn is surrounded by a slow neutron absorber region. Liquid sodium is used as the primary coolant and circulates through the core which contains the fuel elements. Control of the reactor is accomplished by varying the ability of the reflector region to reflect neutrons back into the core of the reactor. For this purpose the reflector is comprised of moderator and control elements having varying effects on reactivity, the control elements being arranged and actuated by groups to give regulation, shim, and safety control.

  10. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Fermi, E.; Szilard, L.

    1957-09-24

    Reactors of the type employing plates of natural uranium in a moderator are discussed wherein the plates are um-formly disposed in parallel relationship to each other thereby separating the moderator material into distinct and individual layers. Each plate has an uninterrupted sunface area substantially equal to the cross-sectional area of the active portion of the reactor, the particular size of the plates and the volume ratio of moderator to uranium required to sustain a chain reaction being determinable from the known purity of these materials and other characteristics such as the predictable neutron losses due to the formation of radioactive elements of extremely high neutron capture cross section.

  11. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Wigner, E.P.; Weinberg, A.W.; Young, G.J.

    1958-04-15

    A nuclear reactor which uses uranium in the form of elongated tubes as fuel elements and liquid as a coolant is described. Elongated tubular uranium bodies are vertically disposed in an efficient neutron slowing agent, such as graphite, for example, to form a lattice structure which is disposed between upper and lower coolant tanks. Fluid coolant tubes extend through the uranium bodies and communicate with the upper and lower tanks and serve to convey the coolant through the uranium body. The reactor is also provided with means for circulating the cooling fluid through the coolant tanks and coolant tubes, suitable neutron and gnmma ray shields, and control means.

  12. Introduction to the theory and analysis of resolved (and unresolved) neutron resonances via SAMMY

    SciTech Connect (OSTI)

    Larson, N.M.

    1998-02-01

    Neutron cross-section data are important for two distinct purposes: First, they provide insight into the nature of matter, thus assisting in the understanding of fundamental physics. Second, they are needed for practical applications (e.g., for calculating when and how a reactor will become critical, or how much shielding is needed for storage of nuclear materials, and for medical applications). Neutron cross section data in the resolved-resonance region are generally obtained by time-of-flight experiments, which must be carefully analyzed if they are to be properly understood and utilized. In this paper, important features of the analysis process are discussed, with emphasis on the particular techniques used in the analysis code SAMMY. Other features of the code are also described; these include such topics as calculation of group cross sections (including covariance matrices), generation and fitting of integral quantities, and extensions into the unresolved-resonance region and higher energy regions.

  13. Introduction to the Theory and Analysis of Resolved (and Unresolved) Neutron Resonances via SAMMY

    SciTech Connect (OSTI)

    Larson, N.

    2000-03-13

    Neutron cross-section data are important for two purposes: First, they provide insight into the nature of matter, increasing our understanding of fundamental physics. Second, they are needed for practical applications (e.g., for calculating when and how a reactor will become critical, or how much shielding is needed for storage of nuclear materials, or for medical applications). Neutron cross section data in the resolved-resonance region are generally obtained by time-of-flight experiments, which must be carefully analyzed if they are to be properly understood and utilized. In this report, important features of the analysis process are discussed, with emphasis on the particular techniques used in the analysis code SAMMY. Other features of the code are also described; these include such topics as calculation of group cross sections (including covariance matrices), generation and fitting of integral quantities, and extensions into the unresolved-resonance region and higher-energy regions.

  14. Introduction to theory and analysis of resolved (and unresolved) neutron resonances via SAMMY

    SciTech Connect (OSTI)

    Larson, N.M.

    1998-07-01

    Neutron cross-section data are important for two distinct purposes: first, they provide insight into the nature of matter, thus assisting in the understanding of fundamental physics; second, they are needed for practical applications (e.g., for calculating when and how a reactor will become critical, or how much shielding is needed for storage of nuclear materials, and for medical applications). Neutron cross section data in the resolved-resonance region are generally obtained by time-of-flight experiments, which must be carefully analyzed if they are to be properly understood and utilized. In this paper, important features of the analysis process are discussed, with emphasis on the particular technique used in the analysis code SAMMY. Other features of the code are also described; these include such topics as calculation of group cross sections (including covariance matrices), generation and fitting of integral quantities, and extensions into the unresolved-resonance region and higher-energy regions.

  15. Physics Thrust Areas

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

    Thrust Areas Physics Thrust Areas Physics Division serves the nation through its broad portfolio of fundamental and applied research. Quality basic science research: critical component of maintaining our capabilities in national security research To further understand the physical world, generate new or improved technology in experimental physics, and establish a physics foundation for current and future Los Alamos programs, Physics Division leverages its expertise and experimental capabilities

  16. Construction of the WSU Epithermal Neutron Filter

    SciTech Connect (OSTI)

    Venhuizen, James Robert; Nigg, David Waler; Tripard, G.

    2002-09-01

    Moderating material has been installed in the original thermal-neutron filter region of the Washington State University (WSU) TRIGA™ type reactor to produce an epithermal-neutron beam. Attention has been focused upon the development of a convenient, local, epithermal-neutron beam facility at WSU for collaborative Idaho National Engineering and Environmental Laboratory (INEEL)/WSU boron neutron capture therapy (BNCT) preclinical research and boronated pharmaceutical screening in cell and animal models. The design of the new facility was performed in a collaborative effort1,2 of WSU and INEEL scientists. This paper summarizes the physical assembly of this filter.

  17. NEUTRONIC REACTORS

    DOE Patents [OSTI]

    Anderson, H.L.

    1958-10-01

    The design of control rods for nuclear reactors are described. In this design the control rod consists essentially of an elongated member constructed in part of a neutron absorbing material and having tube means extending therethrough for conducting a liquid to cool the rod when in use.

  18. Energy Literacy: Essential Principles and Fundamental Concepts...

    Energy Savers [EERE]

    Energy Literacy: Essential Principles and Fundamental Concepts for Energy Education Energy Literacy: Essential Principles and Fundamental Concepts for Energy Education Energy...

  19. Hydrogen Embrittlement Fundamentals, Modeling, and Experiment...

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

    Fundamentals, Modeling, and Experiment Hydrogen Embrittlement Fundamentals, Modeling, and Experiment Embrittlement, under static load could be a result of the synergistic action of ...

  20. Energy Literacy: Essential Principles and Fundamental Concepts...

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

    Energy Literacy: Essential Principles and Fundamental Concepts for Energy Education Energy Literacy: Essential Principles and Fundamental Concepts for Energy Education Energy ...

  1. Fundamentals of materials accounting for nuclear safeguards ...

    Office of Scientific and Technical Information (OSTI)

    Fundamentals of materials accounting for nuclear safeguards Citation Details In-Document Search Title: Fundamentals of materials accounting for nuclear safeguards You are ...

  2. Methods for absorbing neutrons

    DOE Patents [OSTI]

    Guillen, Donna P.; Longhurst, Glen R.; Porter, Douglas L.; Parry, James R.

    2012-07-24

    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.

  3. Results of a Neutronic Simulation of HTR-Proteus Core 4.2 using PEBBED and other INL Reactor Physics Tools: FY-09 Report

    SciTech Connect (OSTI)

    Hans D. Gougar

    2009-08-01

    The Idaho National Laboratorys deterministic neutronics analysis codes and methods were applied to the computation of the core multiplication factor of the HTR-Proteus pebble bed reactor critical facility. A combination of unit cell calculations (COMBINE-PEBDAN), 1-D discrete ordinates transport (SCAMP), and nodal diffusion calculations (PEBBED) were employed to yield keff and flux profiles. Preliminary results indicate that these tools, as currently configured and used, do not yield satisfactory estimates of keff. If control rods are not modeled, these methods can deliver much better agreement with experimental core eigenvalues which suggests that development efforts should focus on modeling control rod and other absorber regions. Under some assumptions and in 1D subcore analyses, diffusion theory agrees well with transport. This suggests that developments in specific areas can produce a viable core simulation approach. Some corrections have been identified and can be further developed, specifically: treatment of the upper void region, treatment of inter-pebble streaming, and explicit (multiscale) transport modeling of TRISO fuel particles as a first step in cross section generation. Until corrections are made that yield better agreement with experiment, conclusions from core design and burnup analyses should be regarded as qualitative and not benchmark quality.

  4. The use of neutron scattering in nuclear weapons research

    SciTech Connect (OSTI)

    Juzaitis, R.J.

    1995-10-01

    We had a weapons science breakout session last week. Although it would have been better to hold it closer in time to this workshop, I think that it was very valuable. it may have been less of a {open_quotes}short-sleeve{close_quotes} workshop environment than we would have liked, but as the first time two communities-the weapons community and the neutron scattering community- got together, it was a wonderful opportunity to transfer information during the 24 presentations that were made. This report contains discussions on the fundamental analysis of documentation of the enduring stockpile; LANSCE`s contribution to weapons; spallation is critical to understanding; weapons safety assessments; applied nuclear physics requires cross section information; fission models need refinement; and establishing teams on collaborative projects.

  5. Fundamental Interactions - Research - Cyclotron Institute

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

    Fundamental Interactions Production of 46V with MARS. Energy loss versus position on Y axis. The Standard Model, which unifies the strong, electromagnetic and weak forces, has been remarkably successful in describing the interactions of quarks and leptons. However, the model is incomplete, and it is the goal of this research program to sensitively probe its limits. Though in most cases we use the nucleus as a micro-laboratory for testing the Standard Model, the implications of the results extend

  6. Neutron reflecting supermirror structure

    DOE Patents [OSTI]

    Wood, James L.

    1992-01-01

    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.

  7. Neutron reflecting supermirror structure

    DOE Patents [OSTI]

    Wood, J.L.

    1992-12-01

    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.

  8. NEUTRONIC REACTORS

    DOE Patents [OSTI]

    Vernon, H.C.

    1959-01-13

    A neutronic reactor of the heterogeneous, fluid cooled tvpe is described. The reactor is comprised of a pressure vessel containing the moderator and a plurality of vertically disposed channels extending in spaced relationship through the moderator. Fissionable fuel material is placed within the channels in spaced relationship thereto to permit circulation of the coolant fluid. Separate means are provided for cooling the moderator and for circulating a fluid coolant thru the channel elements to cool the fuel material.

  9. Bridging the Gap between Fundamental Physics and Chemistry and...

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

    2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005deerassanis.pdf (1.42 MB) More Documents & Publications Computationally Efficient Modeling ...

  10. 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, breaking a world record. July 10, 2012 Tom Hurry of Plasma Physics adjusts the target positioner and particle beam diagnostics prior to an experiment at Trident. Tom Hurry of Plasma Physics adjusts the target positioner and particle beam diagnostics prior to an experiment at Trident. Contact Kevin Roark Communications

  11. Conducting Polymers for Neutron Detection

    SciTech Connect (OSTI)

    Kimblin, Clare; Miller, Kirk; Vogel, Bob; Quam, Bill; McHugh, Harry; Anthony, Glen; Mike, Grover

    2007-12-01

    Conjugated polymers have emerged as an attractive technology for large-area electronic applications. As organic semiconductors, they can be used to make large-area arrays of diodes or transistors using fabrication techniques developed for polymer coatings, such as spraying and screen-printing. We have demonstrated both neutron and alpha detection using diodes made from conjugated polymers and have done preliminary work to integrate a boron carbide layer into the conventional polymer device structure to capture thermal neutrons. The polymer devices appear to be insensitive to gamma rays, due to their small physical thickness and low atomic number.

  12. The synchronous active neutron detection assay system

    SciTech Connect (OSTI)

    Pickrell, M.M.; Kendall, P.K.

    1994-08-01

    We have begun to develop a novel technique for active neutron assay of fissile material in spent nuclear fuel. This approach will exploit a 14-MeV neutron generator developed by Schlumberger. The technique, termed synchronous active neutron detection (SAND), follows a method used routinely in other branches of physics to detect very small signals in presence of large backgrounds. Synchronous detection instruments are widely available commercially and are termed ``lock-in`` amplifiers. We have implemented a digital lock-in amplifier in conjunction with the Schlumberger neutron generator to explore the possibility of synchronous detection with active neutrons. The Schlumberger system can operate at up to a 50% duty factor, in effect, a square wave of neutron yield. Results are preliminary but promising. The system is capable of resolving the fissile material contained in a small fraction of the fuel rods in a cold fuel assembly; it also appears resilient to background neutron interference. The interrogating neutrons appear to be non-thermal and penetrating. Work remains to fully explore relevant physics and optimize instrument design.

  13. 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.

  14. NEUTRON SOURCE

    DOE Patents [OSTI]

    Reardon, W.A.; Lennox, D.H.; Nobles, R.G.

    1959-01-13

    A neutron source of the antimony--beryllium type is presented. The source is comprised of a solid mass of beryllium having a cylindrical recess extending therein and a cylinder containing antimony-124 slidably disposed within the cylindrical recess. The antimony cylinder is encased in aluminum. A berylliunn plug is removably inserted in the open end of the cylindrical recess to completely enclose the antimony cylinder in bsryllium. The plug and antimony cylinder are each provided with a stud on their upper ends to facilitate handling remotely.

  15. NEUTRON COUNTER

    DOE Patents [OSTI]

    Curtis, C.D.; Carlson, R.L.; Tubinis, M.P.

    1958-07-29

    An ionization chamber instrument is described for cylindrical electrodes with an ionizing gag filling the channber. The inner electrode is held in place by a hermetic insulating seal at one end of the outer electrode, the other end of the outer electrode being closed by a gas filling tube. The outer surface of the inner electrode is coated with an active material which is responsive to neutron bombardment, such as uranium235 or boron-10, to produce ionizing radiations in the gas. The transverse cross sectional area of the inner electrode is small in relation to that of the channber whereby substantially all of the radiations are directed toward the outer electrode.

  16. Fundamental studies of polymer filtration

    SciTech Connect (OSTI)

    Smith, B.F.; Lu, M.T.; Robison, T.W.; Rogers, Y.C.; Wilson, K.V.

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The objectives of this project were (1) to develop an enhanced fundamental understanding of the coordination chemistry of hazardous-metal-ion complexation with water-soluble metal-binding polymers, and (2) to exploit this knowledge to develop improved separations for analytical methods, metals processing, and waste treatment. We investigated features of water-soluble metal-binding polymers that affect their binding constants and selectivity for selected transition metal ions. We evaluated backbone polymers using light scattering and ultrafiltration techniques to determine the effect of pH and ionic strength on the molecular volume of the polymers. The backbone polymers were incrementally functionalized with a metal-binding ligand. A procedure and analytical method to determine the absolute level of functionalization was developed and the results correlated with the elemental analysis, viscosity, and molecular size.

  17. Comparison of IUPAC k0 Values and Neutron Cross Sections to Determine a Self-consistent Set of Data for Neutron Activation Analysis

    SciTech Connect (OSTI)

    Firestone, Richard B; Revay, Zsolt

    2009-12-01

    Independent databases of nuclear constants for Neutron Activation Analysis (NAA) have been independently maintained by the physics and chemistry communities for many year. They contain thermal neturon cross sections s0, standardization values k0, and transition probabilities Pg. Chemistry databases tend to rely upon direct measurements of the nuclear constants k0 and Pg which are often published in chemistry journals while the physics databases typically include evaluated s0 and Pg data from a variety of experiments published mainly in physics journals. The IAEA/LBNL Evaluated Gamma-ray Activation File (EGAF) also contains prompt and delayed g-ray cross sections sg from Prompt Gamma-ray Activation Analysis (PGAA) measurements that can also be used to determine k0 and s0 values. As a result several independent databases of fundamental constants for NAA have evolved containing slightly different and sometimes discrepant results. An IAEA CRP for a Reference Database for Neutron Activation Analysis was established to compare these databases and investigate the possibilitiy of producing a self-consistent set of s0, k0, sg, and Pg values for NAA and other applications. Preliminary results of this IAEA CRP comparison are given in this paper.

  18. Fundamentals of metals joining with lasers

    SciTech Connect (OSTI)

    Jellison, J.L.

    1991-01-01

    The intrinsic characteristic of a laser as a metals joining heat source is high intensity (high irradiance). Other advantages stem from the ability to optically manipulate the beam and the inertness of light. Optimal application of laser technology to metals joining is supported by a fundamental understanding of the physics of the process. The interaction of the laser beam with metals is highly materials and process dependent. Metals joining with lasers in a absence of an understanding of beam-materials interactions would appear to be a highly unpredictable process. This is because of the complexity of beam-material interactions. For example, absorptivity varies by more than an order of magnitude as a function of alloy, temperature, oxide thickness, and laser wavelength. Also, in most laser welding and brazing processing, evaporation of metal creates a significant plume, and beam-plume interactions can markedly alter the spatial distribution of energy at the plume-metal interface. The probability of the beam being absorbed by the plume increases with the square of the wavelength, whereas the propensity for scattering of the beam by particles in the beam is inversely proportional to wavelength. Also, the beam can be refracted due to thermal and compositional gradients in the plume. In selecting a laser process for a given application, understanding each of these physical effects and others is helpful. In many ways, the physics of metals joining with lasers is only qualitatively understood at the present time. This paper overviews the present understanding of the process and identifies areas where research is required to clarify our process understanding.

  19. Search for the Neutron Electric Dipole Moment

    SciTech Connect (OSTI)

    Plaster, Brad

    2010-08-04

    Searches for the neutron electric dipole moment (EDM) are motivated by their highly suppressed Standard Model value. The observation of a non-zero signal in the next generation of experiments would point unambiguously to the existence of new physics beyond the Standard Model. Several ongoing efforts worldwide hold the potential for an up to two-orders-of-magnitude improvement beyond the current upper limit on the neutron EDM of 2.9x10{sup -6} e-cm. In this talk, I review the basic measurement principles of neutron EDM searches, then discuss a new experiment to be carried out in the United States at the Spallation Neutron Source with ultracold neutrons and an in-situ '3He''co-magnetometer'.

  20. Government Contracting Fundamentals | Department of Energy

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

    Services » Funding » Small Business Program » Government Contracting Fundamentals Government Contracting Fundamentals EERE's Government Contracting Fundamentals lists useful government contracting resource links and descriptions for small businesses. Government Contracting Fundamentals (382.97 KB) More Documents & Publications Top 10 Tips for Contracting with the DOE Doing Business with the Office of Energy Efficiency and Renewable Energy: Frequently Asked Questions U.S. Department of

  1. Fundamental studies of fusion plasmas

    SciTech Connect (OSTI)

    Aamodt, R.E.; Catto, P.J.; D'Ippolito, D.A.; Myra, J.R.; Russell, D.A.

    1993-04-27

    Work on ICRF interaction with the edge plasma is reported. ICRF generated convective cells have been established as an important mechanism for influencing edge transport and interaction with the H-mode, and for controlling profiles in the tokamak scrape-off-layer. Power dissipation by rf sheaths has been shown to be significant for some misaligned ICRF and IIBW antenna systems. Near-field antenna sheath work has been extended to the far-field case, important for experiments with low single pass absorption. Impurity modeling and Faraday screen design support has been provided for the ICRF community. In the area of core-ICRF physics, the kinetic theory of heating by applied ICRF waves has been extended to retain important geometrical effects relevant to modeling minority heated tokamak plasmas, thereby improving on the physics base that is standard in presently employed codes. Both the quasilinear theory of ion heating, and the plasma response function important in wave codes have been addressed. In separate studies, it has been shown that highly anisotropic minority heated plasmas can give rise to unstable field fluctuations in some situations. A completely separate series of studies have contributed to the understanding of tokamak confinement physics. Additionally, a diffraction formalism has been produced which will be used to access the focusability of lower hybrid, ECH, and gyrotron scattering antennas in dynamic plasma configurations.

  2. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Stewart, H.B.

    1958-12-23

    A nuclear reactor of the type speclfically designed for the irradiation of materials is discussed. In this design a central cyllndrical core of moderating material ls surrounded by an active portlon comprlsed of an annular tank contalning fissionable material immersed ln a liquid moderator. The active portion ls ln turn surrounded by a reflector, and a well ls provided in the center of the core to accommodate the materlals to be irradiated. The over-all dimensions of the core ln at least one plane are equal to or greater than twice the effective slowing down length and equal to or less than twlce the effective diffuslon length for neutrons in the core materials.

  3. NEUTRONIC REACTORS

    DOE Patents [OSTI]

    Wigner, E.P.; Young, G.J.

    1958-10-14

    A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.

  4. Christmas burst reveals neutron star collision

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

    Christmas burst reveals neutron star collision Christmas burst reveals neutron star collision Called the Christmas Burst, GRB 101225A was freakishly lengthy and it produced radiation at unusually varying wavelengths. December 1, 2011 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los

  5. Neutron reflecting supermirror structure

    DOE Patents [OSTI]

    Wood, James L.

    1992-01-01

    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.

  6. Ultrasonics: Fundamentals, Technologies, and Applications

    SciTech Connect (OSTI)

    Ensminger, Dale; Bond, Leonard J.

    2011-09-17

    This is a new edition of a bestselling industry reference. Discusses the science, technology, and applications of low and high power ultrasonics, including industrial implementations and medical uses. Reviews the basic equations of acoustics, starting from basic wave equations and their applications. New material on property determination, inspection of metals (NDT) and non-metals, imaging, process monitoring and control. Expanded discussion of transducers, transducer wave-fields, scattering, attenuation and measurement systems and models. New material that discusses high power ultrasonics - in particular using mechanical effects and sonochemistry, including applications to nano-materials. Examines diagnosis, therapy, and surgery from a technology and medical physics perspective.

  7. Fundamental mechanisms of micromachine reliability

    SciTech Connect (OSTI)

    DE BOER,MAARTEN P.; SNIEGOWSKI,JEFFRY J.; KNAPP,JAMES A.; REDMOND,JAMES M.; MICHALSKE,TERRY A.; MAYER,THOMAS K.

    2000-01-01

    Due to extreme surface to volume ratios, adhesion and friction are critical properties for reliability of Microelectromechanical Systems (MEMS), but are not well understood. In this LDRD the authors established test structures, metrology and numerical modeling to conduct studies on adhesion and friction in MEMS. They then concentrated on measuring the effect of environment on MEMS adhesion. Polycrystalline silicon (polysilicon) is the primary material of interest in MEMS because of its integrated circuit process compatibility, low stress, high strength and conformal deposition nature. A plethora of useful micromachined device concepts have been demonstrated using Sandia National Laboratories' sophisticated in-house capabilities. One drawback to polysilicon is that in air the surface oxidizes, is high energy and is hydrophilic (i.e., it wets easily). This can lead to catastrophic failure because surface forces can cause MEMS parts that are brought into contact to adhere rather than perform their intended function. A fundamental concern is how environmental constituents such as water will affect adhesion energies in MEMS. The authors first demonstrated an accurate method to measure adhesion as reported in Chapter 1. In Chapter 2 through 5, they then studied the effect of water on adhesion depending on the surface condition (hydrophilic or hydrophobic). As described in Chapter 2, they find that adhesion energy of hydrophilic MEMS surfaces is high and increases exponentially with relative humidity (RH). Surface roughness is the controlling mechanism for this relationship. Adhesion can be reduced by several orders of magnitude by silane coupling agents applied via solution processing. They decrease the surface energy and render the surface hydrophobic (i.e. does not wet easily). However, only a molecular monolayer coats the surface. In Chapters 3-5 the authors map out the extent to which the monolayer reduces adhesion versus RH. They find that adhesion is independent of

  8. Features of MCNP6 Relevant to Medical Radiation Physics

    SciTech Connect (OSTI)

    Hughes, H. Grady III; Goorley, John T.

    2012-08-29

    MCNP (Monte Carlo N-Particle) is a general-purpose Monte Carlo code for simulating the transport of neutrons, photons, electrons, positrons, and more recently other fundamental particles and heavy ions. Over many years MCNP has found a wide range of applications in many different fields, including medical radiation physics. In this presentation we will describe and illustrate a number of significant recently-developed features in the current version of the code, MCNP6, having particular utility for medical physics. Among these are major extensions of the ability to simulate large, complex geometries, improvement in memory requirements and speed for large lattices, introduction of mesh-based isotopic reaction tallies, advances in radiography simulation, expanded variance-reduction capabilities, especially for pulse-height tallies, and a large number of enhancements in photon/electron transport.

  9. Investigation of fundamental limits to beam brightness available from photoinjectors

    SciTech Connect (OSTI)

    Bazarov, Ivan

    2015-07-09

    The goal of this project was investigation of fundamental limits to beam brightness available from photoinjectors. This basic research in accelerator physics spanned over 5 years aiming to extend the fundamental understanding of high average current, low emittance sources of relativistic electrons based on photoemission guns, a necessary prerequisite for a new generation of coherent X-ray synchrotron radiation facilities based on continuous duty superconducting linacs. The program focused on two areas critical to making advances in the electron source performance: 1) the physics of photocathodes for the production of low emittance electrons and 2) control of space charge forces in the immediate vicinity to the cathode via 3D laser pulse shaping.

  10. Lighting fundamentals handbook: Lighting fundamentals and principles for utility personnel

    SciTech Connect (OSTI)

    Eley, C.; Tolen, T. Associates, San Francisco, CA ); Benya, J.R. )

    1992-12-01

    Lighting accounts for approximately 30% of overall electricity use and demand in commercial buildings. This handbook for utility personnel provides a source of basic information on lighting principles, lighting equipment, and other considerations related to lighting design. The handbook is divided into three parts. Part One, Physics of Light, has chapters on light, vision, optics, and photometry. Part Two, Lighting Equipment and Technology, focuses on lamps, luminaires, and lighting controls. Part Three, Lighting Design Decisions, deals with the manner in which lighting design decisions are made and reviews relevant methods and issues. These include the quantity and quality of light needed for visual tasks, calculation methods for verifying that lighting needs are satisfied, lighting economics and methods for evaluating investments in efficient lighting systems, and miscellaneous design issues including energy codes, power quality, photobiology, and disposal of lighting equipment. The handbook contains a discussion of the role of the utility in promoting the use of energy-efficient lighting. The handbook also includes a lighting glossary and a list of references for additional information. This convenient and comprehensive handbook is designed to enable utility lighting personnel to assist their customers in developing high-quality, energy-efficient lighting systems. The handbook is not intended to be an up-to-date reference on lighting products and equipment.

  11. Fundamental Symmetries of the Early Universe and the Precision Frontier

    SciTech Connect (OSTI)

    Ramsey-Musolf, Michael J. [Department of Physics, University of Wisconsin-Madison, Madison, WI 53706 (United States) and Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States)

    2009-12-17

    The search for the next Standard Model of fundamental interactions is being carried out at two frontiers: the high energy frontier involving the Tevatron and Large Hadron Collider, and the high precision frontier where the focus is largely on low energy experiments. I discuss the unique and powerful window on new physics provided by the precision frontier and its complementarity to the information we hope to gain from present and future colliders.

  12. The relation between the fundamental scale controlling high-energy interactions of quarks and the proton mass

    SciTech Connect (OSTI)

    Deur, Alexandre; Brodsky, Stanley J.; de Teramond, Guy F.

    2015-04-06

    Quantum Chromodynamics (QCD) provides a fundamental description of the physics binding quarks into protons, neutrons, and other hadrons. QCD is well understood at short distances where perturbative calculations are feasible. Establishing an explicit relation between this regime and the large-distance physics of quark confinement has been a long-sought goal. A major challenge is to relate the parameter Λs, which controls the predictions of perturbative QCD (pQCD) at short distances, to the masses of hadrons. Here we show how new theoretical insights into QCD's behavior at large and small distances lead to an analytical relation between hadronic masses and Λs. The resulting prediction, Λs = 0.341 ± 0.024 GeV agrees well with the experimental value 0.339 ± 0.016 GeV. Conversely, the experimental value of Λs can be used to predict the masses of hadrons, a task which had so far only been accomplished through intensive numerical lattice calculations, requiring several phenomenological input parameters.

  13. Neutron range spectrometer

    DOE Patents [OSTI]

    Manglos, Stephen H.

    1989-06-06

    A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are collimnated 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. The computer solves the following equation in the analysis: ##EQU1## where: N(x).DELTA.x=the number of neutron interactions measured between a position x and x+.DELTA.x, A.sub.i (E.sub.i).DELTA.E.sub.i =the number of incident neutrons with energy between E.sub.i and E.sub.i +.DELTA.E.sub.i, and C=C(E.sub.i)=N .sigma.(E.sub.i) where N=the number density of absorbing atoms in the position sensitive counter means and .sigma. (E.sub.i)=the average cross section of the absorbing interaction between E.sub.i and E.sub.i +.DELTA.E.sub.i.

  14. NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.

    1958-09-01

    This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.

  15. Los Alamos Neutron Science Center gets capacity boost

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

    Neutron Science Center capacity boost Los Alamos Neutron Science Center gets capacity boost The facility can simulate the effects of hundreds or thousands of years of cosmic-ray-induced neutrons in a single hour. December 2, 2010 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los

  16. Neutron streak camera

    DOE Patents [OSTI]

    Wang, C.L.

    1983-09-13

    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.

  17. Neutron streak camera

    DOE Patents [OSTI]

    Wang, Ching L.

    1983-09-13

    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.

  18. Layered semiconductor neutron detectors

    DOE Patents [OSTI]

    Mao, Samuel S; Perry, Dale L

    2013-12-10

    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.

  19. Neutron streak camera

    DOE Patents [OSTI]

    Wang, C.L.

    1981-05-14

    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. Organic metal neutron detector

    DOE Patents [OSTI]

    Butler, M.A.; Ginley, D.S.

    1984-11-21

    A device for detection of neutrons comprises: as an active neutron sensing element, a conductive organic polymer having an electrical conductivity and a cross-section for said neutrons whereby a detectable change in said conductivity is caused by impingement of said neutrons on the conductive organic polymer which is responsive to a property of said polymer which is altered by impingement of said neutrons on the polymer; and means for associating a change in said alterable property with the presence of neutrons at the location of said device.

  1. Spallation Neutron Source | Neutron Science at ORNL

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

    The recently commissioned 11 Tesla horizontal field magnet at GP-SANS will enable advanced neutron scattering research. Credit: Genevieve MartinORNL. 11 Tesla Magnet Commissioned ...

  2. Neutronic Reactor Design to Reduce Neutron Loss

    DOE Patents [OSTI]

    Miles, F. T.

    1961-05-01

    A nuclear reactor construction is described in which an unmoderated layer of the fissionable material is inserted between the moderated portion of the reactor core and the core container steel wall. The wall is surrounded by successive layers of pure fertile material and moderator containing fertile material. The unmoderated layer of the fissionable material will insure that a greater portion of fast neutrons will pass through the steel wall than would thermal neutrons. Since the steel has a smaller capture cross section for the fast neutrons, greater nunnbers of neutrons will pass into the blanket, thereby increasing the over-all efficiency of the reactor. (AEC)

  3. NEUTRONIC REACTOR DESIGN TO REDUCE NEUTRON LOSS

    DOE Patents [OSTI]

    Mills, F.T.

    1961-05-01

    A nuclear reactor construction is described in which an unmoderated layer of the fissionable material is inserted between the moderated portion of the reactor core and the core container steel wall which is surrounded by successive layers of pure fertile material and fertile material having moderator. The unmoderated layer of the fissionable material will insure that a greater portion of fast neutrons will pass through the steel wall than would thermal neutrons. As the steel has a smaller capture cross-section for the fast neutrons, then greater numbers of the neutrons will pass into the blanket thereby increasing the over-all efficiency of the reactor.

  4. Interface Induced Carbonate Mineralization: A Fundamental Geochemical...

    Office of Scientific and Technical Information (OSTI)

    fundamental barrier, other than cation hydration, exists that prevents Mgsup 2+ and ... of water give us a first direct proof to support and quantify the cation hydration effect. ...

  5. Modeling of Geothermal Reservoirs: Fundamental Processes, Computer...

    Open Energy Info (EERE)

    of Geothermal Reservoirs: Fundamental Processes, Computer Simulation and Field Applications Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

  6. Interface Induced Carbonate Mineralization: A Fundamental Geochemical

    Office of Scientific and Technical Information (OSTI)

    Interface Induced Carbonate Mineralization: A Fundamental Geochemical Process Relevant to Carbon Sequestration Teng, H. Henry PI, The George Washington University PI, The George...

  7. "Fundamental Challenges in Solar Energy Conversion" workshop...

    Office of Science (SC) Website

    Fundamental Challenges in Solar Energy Conversion" workshop hosted by LMI-EFRC Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events ...

  8. Fundamental Electroweak Studies using Trapped Ions & Atoms

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

    collaboration performs fundamental electroweak studies on trapped ions & atoms. We use neutral atom and ion trapping techniques at radioactive ion beam facilities here and...

  9. Neutron interaction and their transport with bulk materials

    SciTech Connect (OSTI)

    Rani, Esther Kalpana; Radhika, K.

    2015-05-15

    In the current paper an attempt was made to study and provide fundamental information about neutron interactions that are important to nuclear material measurements. The application of this study is explained about macroscopic interactions with bulk compound materials through a program in DEV C++ language which is done by enabling interaction of neutrons in nature. The output of the entire process depends upon the random number (i.e., incident neutron number), thickness of the material and mean free path as input parameters. Further the current study emphasizes on the usage of materials in shielding.

  10. Dose equivalent neutron dosimeter

    DOE Patents [OSTI]

    Griffith, Richard V.; Hankins, Dale E.; Tomasino, Luigi; Gomaa, Mohamed A. M.

    1983-01-01

    A neutron dosimeter is disclosed which provides a single measurements 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 containing 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. The density of conversion material in the radiator layer is of an amount which is chosen so that the density of tracks produced in the detecting sheet is proportional to the biological damage done by neutrons, regardless of whether the tracks are produced as the result of moderate energy neutrons striking the radiator layer or as the result of higher energy neutrons striking the sheet of track etch material.

  11. Pulsed-neutron monochromator

    DOE Patents [OSTI]

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

    1985-01-01

    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.

  12. Ultrafast neutron detector

    DOE Patents [OSTI]

    Wang, C.L.

    1985-06-19

    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.

  13. Neutron dose equivalent meter

    DOE Patents [OSTI]

    Olsher, Richard H.; Hsu, Hsiao-Hua; Casson, William H.; Vasilik, Dennis G.; Kleck, Jeffrey H.; Beverding, Anthony

    1996-01-01

    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.

  14. Pulsed-neutron monochromator

    DOE Patents [OSTI]

    Mook, H.A. Jr.

    1984-01-01

    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. ULTRASONIC NEUTRON DOSIMETER

    DOE Patents [OSTI]

    Truell, R.; de Klerk, J.; Levy, P.W.

    1960-02-23

    A neutron dosimeter is described which utilizes ultrasonic waves in the megacycle region for determination of the extent of neutron damage in a borosilicate glass through ultrasonic wave velocity and attenuation measurements before and after damage.

  16. New Mexico Center for Particle Physics (NMCPP) -- Task A: Collider Physics; Task A2: Collider Physics; Task B: Particle Astrophysics

    SciTech Connect (OSTI)

    Matthews, John; Seidel, Sally; Gold, Michael

    2013-11-05

    During the period 2010-­‐2012, we conducted particle physics research with the ATLAS and CDF experiments and developed new instrumentation for tracking fundamental particles.

  17. Neutrons - 88-Inch Cyclotron

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

    Neutrons Neutron beams are available at the 88-Inch Cyclotron. Available energies range of from 8 to 30 MeV, with fluxes of up to 1E8 neutrons/cm^2/sec. For more information, please contact Mike Johnson via e-mail at MBJohnson@lbl.gov, or by phone at at (510) 486-4389.

  18. Advanced neutron absorber materials

    DOE Patents [OSTI]

    Branagan, Daniel J.; Smolik, Galen R.

    2000-01-01

    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.

  19. Prototype Neutron Energy Spectrometer

    SciTech Connect (OSTI)

    Stephen Mitchell, Sanjoy Mukhopadhyay, Richard Maurer, Ronald Wolff

    2010-06-16

    The project goals are: (1) Use three to five pressurized helium tubes with varying polyethylene moderators to build a neutron energy spectrometer that is most sensitive to the incident neutron energy of interest. Neutron energies that are of particular interest are those from the fission neutrons (typically around 1-2 MeV); (2) Neutron Source Identification - Use the neutron energy 'selectivity' property as a tool to discriminate against other competing processes by which neutrons are generated (viz. Cosmic ray induced neutron production [ship effect], [a, n] reactions); (3) Determine the efficiency as a function of neutron energy (response function) of each of the detectors, and thereby obtain the composite neutron energy spectrum from the detector count rates; and (4) Far-field data characterization and effectively discerning shielded fission source. Summary of the presentation is: (1) A light weight simple form factor compact neutron energy spectrometer ready to be used in maritime missions has been built; (2) Under laboratory conditions, individual Single Neutron Source Identification is possible within 30 minutes. (3) Sources belonging to the same type of origin viz., (a, n), fission, cosmic cluster in the same place in the 2-D plot shown; and (4) Isotopes belonging to the same source origin like Cm-Be, Am-Be (a, n) or Pu-239, U-235 (fission) do have some overlap in the 2-D plot.

  20. Arsenic activation neutron detector

    DOE Patents [OSTI]

    Jacobs, E.L.

    1980-01-28

    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.

  1. Arsenic activation neutron detector

    DOE Patents [OSTI]

    Jacobs, Eddy L.

    1981-01-01

    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.

  2. Nuclear and Particle Physics, Astrophysics, and Cosmology

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

    Nuclear and Particle Physics, Astrophysics, and Cosmology Providing scientific and technical leadership in fundamental and applied theoretical research on nuclear, particle, ...

  3. UCNA | Ultracold Neutrons at Los Alamos National Laboratory

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

    published an update of the beta-asymmetry with sub-1% precision in 2013. North Carolina State University UCNA Collaboration http:neutron.physics.ncsu.eduUCNAindex.php UCNA UCNA...

  4. UCN tau | Ultracold Neutrons at Los Alamos National Laboratory

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

    UCN The half-life (or lifetime ) of the neutron is intimately connected to many other processes in particle physics and cosmology, such as the abundance of nuclei in the early...

  5. Physics Division progress report, January 1, 1984-September 30, 1986

    SciTech Connect (OSTI)

    Keller, W.E.

    1987-10-01

    This report provides brief accounts of significant progress in development activities and research results achieved by Physics Division personnel during the period January 1, 1984, through September 31, 1986. These efforts are representative of the three main areas of experimental research and development in which the Physics Division serves Los Alamos National Laboratory's and the Nation's needs in defense and basic sciences: (1) defense physics, including the development of diagnostic methods for weapons tests, weapon-related high-energy-density physics, and programs supporting the Strategic Defense Initiative; (2) laser physics and applications, especially to high-density plasmas; and (3) fundamental research in nuclear and particle physics, condensed-matter physics, and biophysics. Throughout the report, emphasis is placed on the design, construction, and application of a variety of advanced, often unique, instruments and instrument systems that maintain the Division's position at the leading edge of research and development in the specific fields germane to its mission. A sampling of experimental systems of particular interest would include the relativistic electron-beam accelerator and its applications to high-energy-density plasmas; pulsed-power facilities; directed energy weapon devices such as free-electron lasers and neutral-particle-beam accelerators; high-intensity ultraviolet and x-ray beam lines at the National Synchrotron Light Source (at Brookhaven National Laboratory); the Aurora KrF ultraviolet laser system for projected use as an inertial fusion driver; antiproton physics facility at CERN; and several beam developments at the Los Alamos Meson Physics Facility for studying nuclear, condensed-matter, and biological physics, highlighted by progress in establishing the Los Alamos Neutron Scattering Center.

  6. Semiconductor neutron detector

    DOE Patents [OSTI]

    Ianakiev, Kiril D.; Littlewood, Peter B.; Blagoev, Krastan B.; Swinhoe, Martyn T.; Smith, James L.; Sullivan, Clair J.; Alexandrov, Boian S.; Lashley, Jason Charles

    2011-03-08

    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.

  7. Neutron scatter camera

    DOE Patents [OSTI]

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

    2010-06-22

    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.

  8. Organic metal neutron detector

    DOE Patents [OSTI]

    Butler, Michael A.; Ginley, David S.

    1987-01-01

    A device for detecting neutrons comprises a layer of conductive polymer sandwiched between electrodes, which may be covered on each face with a neutron transmissive insulating material layer. Conventional electrodes are used for a non-imaging integrating total neutron fluence-measuring embodiment, while wire grids are used in an imaging version of the device. The change in conductivity of the polymer after exposure to a neutron flux is determined in either case to provide the desired data. Alternatively, the exposed conductive polymer layer may be treated with a chemical reagent which selectively binds to the sites altered by neutrons to produce an image of the flux detected.

  9. High energy neutron dosimeter

    DOE Patents [OSTI]

    Rai, K.S.F.

    1994-01-11

    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.

  10. PERSONNEL NEUTRON DOSIMETER

    DOE Patents [OSTI]

    Fitzgerald, J.J.; Detwiler, C.G. Jr.

    1960-05-24

    A description is given of a personnel neutron dosimeter capable of indicating the complete spectrum of the neutron dose received as well as the dose for each neutron energy range therein. The device consists of three sets of indium foils supported in an aluminum case. The first set consists of three foils of indium, the second set consists of a similar set of indium foils sandwiched between layers of cadmium, whereas the third set is similar to the second set but is sandwiched between layers of polyethylene. By analysis of all the foils the neutron spectrum and the total dose from neutrons of all energy levels can be ascertained.

  11. High energy neutron dosimeter

    DOE Patents [OSTI]

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

    1994-01-01

    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.

  12. Neutron activation analysis system

    DOE Patents [OSTI]

    Taylor, M.C.; Rhodes, J.R.

    1973-12-25

    A neutron activation analysis system for monitoring a generally fluid media, such as slurries, solutions, and fluidized powders, including two separate conduit loops for circulating fluid samples within the range of radiation sources and detectors is described. Associated with the first loop is a neutron source that emits s high flux of slow and thermal neutrons. The second loop employs a fast neutron source, the flux from which is substantially free of thermal neutrons. Adjacent to both loops are gamma counters for spectrographic determination of the fluid constituents. Other gsmma sources and detectors are arranged across a portion of each loop for deterMining the fluid density. (Official Gazette)

  13. Adiabatic calorimeter: Fundamentals and application in thermal hazard evaluation

    SciTech Connect (OSTI)

    Yin, Fandong

    1995-12-31

    General equations of kinetics and heat of reaction for an ideal adiabatic calorimeter are developed from fundamental principles with an emphasis on elucidating the critical assumptions associated with these equations. Understanding of the assumptions is of critical importance for correctly applying the equations to an actual adiabatic calorimeter. Utilization of the equations without justifying the assumptions can lead to significant uncertainties in the thermodynamic and kinetic information acquired. In addition, the physical concept of adiabaticity is introduced and defined from the fundamental principles. Its difference and relationship with the thermal inertia ({Phi} factor) are further elucidated in details. Application of the adiabaticity to characterize the degree of achieving adiabatic conditions for both plant-scale reactors and bench-scale calorimeters is discussed. Scale-up of experimental data from the bench-scale adiabatic calorimeters to the plant-scale batch reactors is presented for simple as well as complex reaction systems. 12 refs., 2 figs., 6 tabs.

  14. Review of current neutron detection systems for emergency response

    SciTech Connect (OSTI)

    Mukhopadhyay, Sanjoy; Maurer, Richard; Guss, Paul; Kruschwitz, Craig

    2014-09-05

    Neutron detectors are utilized in a myriad of applications—from safeguarding special nuclear materials (SNM) to determining lattice spacing in soft materials. The transformational changes taking place in neutron detection and imaging techniques in the last few years are largely being driven by the global shortage of helium-3 (3He). This article reviews the status of neutron sensors used specifically for SNM detection in radiological emergency response. These neutron detectors must be highly efficient, be rugged, have fast electronics to measure neutron multiplicity, and be capable of measuring direction of the neutron sources and possibly image them with high spatial resolution. Neutron detection is an indirect physical process: neutrons react with nuclei in materials to initiate the release of one or more charged particles that produce electric signals that can be processed by the detection system. Therefore, neutron detection requires conversion materials as active elements of the detection system; these materials may include boron-10 (10B), lithium-6 (6Li), and gadollinium-157 (157Gd), to name a few, but the number of materials available for neutron detection is limited. However, in recent years, pulse-shape-discriminating plastic scintillators, scintillators made of helium-4 (4He) under high pressure, pillar and trench semiconductor diodes, and exotic semiconductor neutron detectors made from uranium oxide and other materials have widely expanded the parameter space in neutron detection methodology. In this article we will pay special attention to semiconductor-based neutron sensors. Finally, modern microfabricated nanotubes covered inside with neutron converter materials and with very high aspect ratios for better charge transport will be discussed.

  15. Fundamentals of preparative and nonlinear chromatography

    SciTech Connect (OSTI)

    Guiochon, Georges A; Felinger, Attila; Katti, Anita; Shirazi, Dean G

    2006-02-01

    The second edition of Fundamentals of Preparative and Nonlinear Chromatography is devoted to the fundamentals of a new process of purification or extraction of chemicals or proteins widely used in the pharmaceutical industry and in preparative chromatography. This process permits the preparation of extremely pure compounds satisfying the requests of the US Food and Drug Administration. The book describes the fundamentals of thermodynamics, mass transfer kinetics, and flow through porous media that are relevant to chromatography. It presents the models used in chromatography and their solutions, discusses the applications made, describes the different processes used, their numerous applications, and the methods of optimization of the experimental conditions of this process.

  16. NEUTRON DENSITY CONTROL IN A NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Young, G.J.

    1959-06-30

    The method and means for controlling the neutron density in a nuclear reactor is described. It describes the method and means for flattening the neutron density distribution curve across the reactor by spacing the absorbing control members to varying depths in the central region closer to the center than to the periphery of the active portion of the reactor to provide a smaller neutron reproduction ratio in the region wherein the members are inserted, than in the remainder of the reactor thereby increasing the over-all potential power output.

  17. Novel neutron sources at the Radiological Research Accelerator Facility

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

    Xu, Yanping; Garty, G.; Marino, S. A.; Massey, Thomas Neal; Johnson, G. W.; Randers-Pehrson, Gerhard; Brenner, D. J.

    2012-03-16

    Since the 1960s, the Radiological Research Accelerator Facility (RARAF) has been providing researchers in biology, chemistry and physics with advanced irradiation techniques, using charged particles, photons and neutrons. We are currently developing a unique facility at RARAF, to simulate neutron spectra from an improvised nuclear device (IND), based on calculations of the neutron spectrum at 1.5 km from the epicenter of the Hiroshima atom bomb. This is significantly different from a standard fission spectrum, because the spectrum changes as the neutrons are transported through air, and is dominated by neutron energies between 0.05 and 8 MeV. This facility will bemore » based on a mixed proton/deuteron beam impinging on a thick beryllium target. A second, novel facility under development is our new neutron microbeam. The neutron microbeam will, for the first time, provide a kinematically collimated neutron beam, 10-20 micron in diameter. This facility is based on a proton microbeam, impinging on a thin lithium target near the threshold of the Li-7(p,n)Be-7 reaction. Lastly, this novel neutron microbeam will enable studies of neutron damage to small targets, such as single cells, individual organs within small animals or microelectronic components.« less

  18. Review of current neutron detection systems for emergency response

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

    Mukhopadhyay, Sanjoy; Maurer, Richard; Guss, Paul; Kruschwitz, Craig

    2014-09-05

    Neutron detectors are utilized in a myriad of applications—from safeguarding special nuclear materials (SNM) to determining lattice spacing in soft materials. The transformational changes taking place in neutron detection and imaging techniques in the last few years are largely being driven by the global shortage of helium-3 (3He). This article reviews the status of neutron sensors used specifically for SNM detection in radiological emergency response. These neutron detectors must be highly efficient, be rugged, have fast electronics to measure neutron multiplicity, and be capable of measuring direction of the neutron sources and possibly image them with high spatial resolution. Neutronmore » detection is an indirect physical process: neutrons react with nuclei in materials to initiate the release of one or more charged particles that produce electric signals that can be processed by the detection system. Therefore, neutron detection requires conversion materials as active elements of the detection system; these materials may include boron-10 (10B), lithium-6 (6Li), and gadollinium-157 (157Gd), to name a few, but the number of materials available for neutron detection is limited. However, in recent years, pulse-shape-discriminating plastic scintillators, scintillators made of helium-4 (4He) under high pressure, pillar and trench semiconductor diodes, and exotic semiconductor neutron detectors made from uranium oxide and other materials have widely expanded the parameter space in neutron detection methodology. In this article we will pay special attention to semiconductor-based neutron sensors. Finally, modern microfabricated nanotubes covered inside with neutron converter materials and with very high aspect ratios for better charge transport will be discussed.« less

  19. Lujan Neutron Scattering Center

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

    responds to radiological incident August 27, 2012 The Laboratory is investigating 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 spread of Technetium 99 by employees and contractors at the Lujan Neutron Scattering Center at the Los Alamos Neutron Science Center (LANSCE), a multidisciplinary accelerator facility used for both civilian and national security research. The

  20. 2010 Neutron Review: ORNL Neutron Sciences Progress Report (Technical

    Office of Scientific and Technical Information (OSTI)

    Report) | SciTech Connect Technical Report: 2010 Neutron Review: ORNL Neutron Sciences Progress Report Citation Details In-Document Search Title: 2010 Neutron Review: ORNL Neutron Sciences Progress Report During 2010, the Neutron Sciences Directorate focused on producing world-class science, while supporting the needs of the scientific community. As the instrument, sample environment, and data analysis tools at High Flux Isotope Reactor (HFIR ) and Spallation Neutron Source (SNS) have grown

  1. Fundamental Symmetries of the Early Universe and the Precision Frontier

    SciTech Connect (OSTI)

    Ramsey-Musolf, Michael (University of Wisconsin) [University of Wisconsin

    2011-03-02

    The quest to explain nature's fundamental interactions and how they shaped the evolution of the universe is one of the most compelling in physics. The standard model of particle physics provides a partial explanation, but we know that it must be part of a larger, more complete framework. Experiments hoping to uncover details of the 'new standard model' are being carried out at two frontiers: the high energy frontier and the high precision frontier. In this talk, I discuss the theoretical implications of some of the key up-coming experiments at the precision frontier. I focus in particular on what they may teach us about the origin of matter and the possible existence of new forces that were important at earlier times in the evolution of the cosmos. I will also comment on how they complement experiments at the energy frontier.

  2. Fast Neutron Detection Evaluation

    SciTech Connect (OSTI)

    McKigney, Edward A.; Stange, Sy

    2014-03-17

    These slides present a summary of previous work, conclusions, and anticipated schedule for the conclusion of our fast neutron detection evaluation.

  3. Neutron detection apparatus

    DOE Patents [OSTI]

    Kopp, Manfred K.; Valentine, Kenneth H.

    1983-01-01

    An atomic fission counting apparatus used for neutron detection is provided with spirally curved electrode plates uniformly spaced apart in a circular array and coated with fissile material.

  4. Magnetization of neutron matter

    SciTech Connect (OSTI)

    Bigdeli, M.

    2011-09-21

    In this paper, we compute magnetization of neutron matter at strong magnetic field using the lowest order constrained variational (LOCV) technique.

  5. The synchronous active neutron detection system for spent fuel assay

    SciTech Connect (OSTI)

    Pickrell, M.M.; Kendall, P.K.

    1994-10-01

    The authors have begun to develop a novel technique for active neutron assay of fissile material in spent nuclear fuel. This approach will exploit the unique operating features of a 14-MeV neutron generator developed by Schlumberger. This generator and a novel detection system will be applied to the direct measurement of the fissile material content in spent fuel in place of the indirect measures used at present. The technique they are investigating is termed synchronous active neutron detection (SAND). It closely follows a method that has been used routinely in other branches of physics to detect very small signals in the presence of large backgrounds. Synchronous detection instruments are widely available commercially and are termed {open_quotes}lock-in{close_quotes} amplifiers. The authors have implemented a digital lock-in amplifier in conjunction with the Schlumberger neutron generator to explore the possibility of synchronous detection with active neutrons. This approach is possible because the Schlumberger system can operate at up to a 50% duty factor, in effect, a square wave of neutron yield. The results to date are preliminary but quite promising. The system is capable of resolving the fissile material contained in a small fraction of the fuel rods in a cold fuel assembly. It also appears to be quite resilient to background neutron interference. The interrogating neutrons appear to be nonthermal and penetrating. Although a significant amount of work remains to fully explore the relevant physics and optimize the instrument design, the underlying concept appears sound.

  6. Neutron and Nuclear Science News

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

    News Recent news and events related to neutron and nuclear science at LANSCE. Neutron and Nuclear Science News Links Neutron and Nuclear Science News Media Links Profiles Events at LANSCE

  7. PNNL: Staff Search - Fundamental & Computational Sciences Directorate

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

    Divisions Advanced Computing, Mathematics & Data Atmospheric Sciences & Global Change Biological Sciences Physical Sciences User Facilities Environmental Molecular Sciences ...

  8. DOE Fundamentals Handbook: Mathematics, Volume 1

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Mathematics Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of mathematics and its application to facility operation. The handbook includes a review of introductory mathematics and the concepts and functional use of algebra, geometry, trigonometry, and calculus. Word problems, equations, calculations, and practical exercises that require the use of each of the mathematical concepts are also presented. This information will provide personnel with a foundation for understanding and performing basic mathematical calculations that are associated with various DOE nuclear facility operations.

  9. DOE Fundamentals Handbook: Mathematics, Volume 2

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Mathematics Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of mathematics and its application to facility operation. The handbook includes a review of introductory mathematics and the concepts and functional use of algebra, geometry, trigonometry, and calculus. Word problems, equations, calculations, and practical exercises that require the use of each of the mathematical concepts are also presented. This information will provide personnel with a foundation for understanding and performing basic mathematical calculations that are associated with various DOE nuclear facility operations.

  10. DOE Fundamentals Handbook: Electrical Science, Volume 4

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Electrical Science Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of electrical theory, terminology, and application. The handbook includes information on alternating current (AC) and direct current (DC) theory, circuits, motors, and generators; AC power and reactive transformers; and electrical test components; batteries; AC and DC voltage regulators; instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment.

  11. DOE Fundamentals Handbook: Electrical Science, Volume 2

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Electrical Science Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding terminology, and application. The handbook includes information on alternating current (AC) and direct current (DC) theory, circuits, motors, and generators; AC power and reactive components; batteries; AC and DC voltage regulators; transformers; and electrical test instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment.

  12. DOE Fundamentals Handbook: Electrical Science, Volume 3

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Electrical Science Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of electrical theory, terminology, and application. The handbook includes information on alternating current (AC) and direct current (DC) theory, circuits, motors and generators; AC power and reactive components; batteries; AC and DC voltage regulators; transformers; and electrical test instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment.

  13. DOE Fundamentals Handbook: Electrical Science, Volume 1

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Electrical Science Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of electrical theory, terminology, and application. The handbook includes information on alternating current (AC) and direct current (DC) theory, circuits, motors, and generators; AC power and reactive components; batteries; AC and DC voltage regulators; transformers; and electrical test instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment.

  14. Inquiring Minds - Questions About Physics

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

    Pure Antineutron Beams Hello, I am a physics student in Germany. I haven't had particle physics yet, so I'd be glad if you answered me one question: How do you create more or less pure anti-neutron beams in your accelerator?? I'm sure it's possible somehow but I just don't know the way to relize that. The "options" I got to know by now: collision of anti-protons with carbon nuclei can result in anti-neutrons decay of lambda-particles (how would you create them?) I guess the main

  15. Physics Division progress report for period ending June 30, 1981

    SciTech Connect (OSTI)

    Not Available

    1981-11-01

    Progress is reported in detail in the following areas: Holifield Heavy-Ion Research Facility, nuclear physics, the UNISOR program, neutron physics, theoretical physics, the Nuclear Data Project, atomic and plasma physics, and high energy physics. Publications are listed. Separate abstracts were prepared for 34 papers. (WHK)

  16. Schoenborn wins Bau Neutron Award

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

    of LANL's Bioenergy and Biome Sciences group, to receive the 2016 Bau Neutron Diffraction Award. The award recognizes exceptional research achievement in neutron...

  17. CASL - Analysis of Two-Dimensional Lattice Physics

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

    Analysis of Two-Dimensional Lattice Physics CASL is developing the Virtual Environment for Reactor Applications (VERA) as a key capability to support the analysis of the CASL Challenge Problems. VERA will include a range of physics modeling capabilities necessary to model reactors, including neutronics, thermal hydraulics, fuel performance, and coolant chemistry. Lattice physics analyses, utilizing the newly-developed Michigan lattice physics neutronics capability in MPACT 1.0, are important to

  18. Neutron irradiation induced amorphization of silicon carbide

    SciTech Connect (OSTI)

    Snead, L.L.; Hay, J.C.

    1998-09-01

    This paper provides the first known observation of silicon carbide fully amorphized under neutron irradiation. Both high purity single crystal hcp and high purity, highly faulted (cubic) chemically vapor deposited (CVD) SiC were irradiated at approximately 60 C to a total fast neutron fluence of 2.6 {times} 10{sup 25} n/m{sup 2}. Amorphization was seen in both materials, as evidenced by TEM, electron diffraction, and x-ray diffraction techniques. Physical properties for the amorphized single crystal material are reported including large changes in density ({minus}10.8%), elastic modulus as measured using a nanoindentation technique ({minus}45%), hardness as measured by nanoindentation ({minus}45%), and standard Vickers hardness ({minus}24%). Similar property changes are observed for the critical temperature for amorphization at this neutron dose and flux, above which amorphization is not possible, is estimated to be greater than 130 C.

  19. Novel Materials and Devices for Solid-State Neutron Detection

    SciTech Connect (OSTI)

    Manginell, Ronald P.; Pfeifer, Kent B.

    2015-11-01

    There is a need in many fields, such as nuclear medicine, non-proliferation, energy exploration, national security, homeland security, nuclear energy, etc, for miniature, thermal neutron detectors. Until recently, thermal neutron detection has required physically large devices to provide sufficient neutron interaction and transduction signal. Miniaturization would allow broader use in the fields just mentioned and open up other applications potentially. Recent research shows promise in creating smaller neutron detectors through the combination of high-neutron-cross-section converter materials and solid-state devices. Yet, till recently it is difficult to measure low neutron fluxes by solidstate means given the need for optimized converter materials (purity, chemical composition and thickness) and a lack of designs capable of efficient transduction of the neutron conversion products (x-rays, electrons, gamma rays). Gadolinium-based semiconductor heterojunctions have detected electrons produced by Gd-neutron reactions but only at high neutron fluxes. One of the main limitations to this type of approach is the use of thin converter layers and the inability to utilize all the conversion products. In this LDRD we have optimized the converter material thickness and chemical composition to improve capture of conversion electrons and have detected thermal neutrons with high fidelity at low flux. We are also examining different semiconductor materials and converter materials to attempt to capture a greater percentage of the conversion electrons, both low and higher energy varieties. We have studied detector size and bias scaling, and cross-sensitivity to xrays and shown that we can detect low fluxes of thermal neutrons in less than 30 minutes with high selectivity by our approach. We are currently studying improvements in performance with direct placement of the Gd converter on the detector. The advancement of sensitive, miniature neutron detectors will have benefits in

  20. Neutron capture therapies

    DOE Patents [OSTI]

    Yanch, Jacquelyn C.; Shefer, Ruth E.; Klinkowstein, Robert E.

    1999-01-01

    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.

  1. Compact neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Lou, Tak Pui

    2005-03-22

    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.

  2. Prequantum Classical Statistical Field Theory: Fundamentals

    SciTech Connect (OSTI)

    Khrennikov, Andrei

    2011-03-28

    We present fundamentals of a prequantum model with hidden variables of the classical field type. In some sense this is the comeback of classical wave mechanics. Our approach also can be considered as incorporation of quantum mechanics into classical signal theory. All quantum averages (including correlations of entangled systems) can be represented as classical signal averages and correlations.

  3. Epithermal Neutron Source for Neutron Resonance Spectroscopy...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 36 MATERIALS SCIENCE; 42 ENGINEERING; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 70 PLASMA ...

  4. Pocked surface neutron detector

    DOE Patents [OSTI]

    McGregor, Douglas; Klann, Raymond

    2003-04-08

    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.

  5. NEUTRON SHIELDING STRUCTURE

    DOE Patents [OSTI]

    Mattingly, J.T.

    1962-09-25

    A lightweight neutron shielding structure comprises a honeycomb core which is filled with a neutron absorbing powder. The honeycomb core is faced with parallel planar facing sheets to form a lightweight rigid unit. Suitable absorber powders are selected from among the following: B, B/sub 4/C, B/sub 2/O/ sub 3/, CaB/sub 6/, Li/sub 2/CO3, LiOH, LiBO/sub 2/, Li/s ub 2/O. The facing sheets are constructed of a neutron moderating material, so that fast neutrons will be moderated while traversing the facing sheets, and ultimately be absorbed by the absorber powder in the honeycomb. Beryllium is a preferred moderator material for use in the facing sheets. The advantage of the structure is that it combines the rigidity and light weight of a honeycomb construction with the neutron absorption properties of boron and lithium. (AEC)

  6. Pulsed neutron detector

    DOE Patents [OSTI]

    Robertson, deceased, J. Craig; Rowland, Mark S.

    1989-03-21

    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.

  7. Biological effectiveness of neutrons: Research needs

    SciTech Connect (OSTI)

    Casarett, G.W.; Braby, L.A.; Broerse, J.J.; Elkind, M.M.; Goodhead, D.T.; Oleinick, N.L.

    1994-02-01

    The goal of this report was to provide a conceptual plan for a research program that would provide a basis for determining more precisely the biological effectiveness of neutron radiation with emphasis on endpoints relevant to the protection of human health. This report presents the findings of the experts for seven particular categories of scientific information on neutron biological effectiveness. Chapter 2 examines the radiobiological mechanisms underlying the assumptions used to estimate human risk from neutrons and other radiations. Chapter 3 discusses the qualitative and quantitative models used to organize and evaluate experimental observations and to provide extrapolations where direct observations cannot be made. Chapter 4 discusses the physical principles governing the interaction of radiation with biological systems and the importance of accurate dosimetry in evaluating radiation risk and reducing the uncertainty in the biological data. Chapter 5 deals with the chemical and molecular changes underlying cellular responses and the LET dependence of these changes. Chapter 6, in turn, discusses those cellular and genetic changes which lead to mutation or neoplastic transformation. Chapters 7 and 8 examine deterministic and stochastic effects, respectively, and the data required for the prediction of such effects at different organizational levels and for the extrapolation from experimental results in animals to risks for man. Gaps and uncertainties in this data are examined relative to data required for establishing radiation protection standards for neutrons and procedures for the effective and safe use of neutron and other high-LET radiation therapy.

  8. Toward A Fundamental Understanding Of Nuclear Reactions And Exotic...

    Office of Scientific and Technical Information (OSTI)

    Conference: Toward A Fundamental Understanding Of Nuclear Reactions And Exotic Nuclei Citation Details In-Document Search Title: Toward A Fundamental Understanding Of Nuclear ...

  9. Nanoscale imaging of fundamental Li battery chemistry: solid...

    Office of Scientific and Technical Information (OSTI)

    Nanoscale imaging of fundamental Li battery chemistry: solid-electrolyte interphase ... Citation Details In-Document Search Title: Nanoscale imaging of fundamental Li battery ...

  10. fundamental Modeling and Experimental Studies of Acicular Mullite...

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

    fundamental Modeling and Experimental Studies of Acicular Mullite Diesel Particulate Filters fundamental Modeling and Experimental Studies of Acicular Mullite Diesel Particulate ...

  11. Fundamentals of Monte Carlo (Technical Report) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Fundamentals of Monte Carlo Citation Details In-Document Search Title: Fundamentals of Monte Carlo Authors: Wollaber, Allan Benton 1 + Show Author Affiliations Los Alamos ...

  12. EERE Success Story-Fundamental Studies in Catalysis Enabled the...

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

    Fundamental Studies in Catalysis Enabled the use of Efficient "Lean-Burn" Engines for Vehicle Transportation EERE Success Story-Fundamental Studies in Catalysis Enabled the use of ...

  13. Fundamental New Insight Into Material for Optical-Switching ...

    Office of Science (SC) Website

    Fundamental New Insight Into Material for Optical-Switching Basic Energy Sciences (BES) ... Fundamental New Insight Into Material for Optical-Switching A triple point, where three ...

  14. Wall of fundamental constants (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Wall of fundamental constants Citation Details In-Document Search Title: Wall of fundamental constants Authors: Olive, Keith A. ; Peloso, Marco ; Uzan, Jean-Philippe Publication ...

  15. Pre-Competitive Catalysis Research: Fundamental Sulfation/Desulfation...

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

    Pre-Competitive Catalysis Research: Fundamental SulfationDesulfation Studies of Lean NOx Traps Pre-Competitive Catalysis Research: Fundamental SulfationDesulfation Studies of...

  16. Fundamental aspects of nuclear reactor fuel elements: solutions...

    Office of Scientific and Technical Information (OSTI)

    Fundamental aspects of nuclear reactor fuel elements: solutions to problems Citation Details In-Document Search Title: Fundamental aspects of nuclear reactor fuel elements: ...

  17. Fundamental aspects of nuclear reactor fuel elements (Technical...

    Office of Scientific and Technical Information (OSTI)

    Fundamental aspects of nuclear reactor fuel elements Citation Details In-Document Search Title: Fundamental aspects of nuclear reactor fuel elements You are accessing a document ...

  18. Vehicle Technologies Office Merit Review 2014: Fundamental Studies...

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

    Fundamental Studies of Lithium-Sulfur Cell Chemistry Vehicle Technologies Office Merit Review 2014: Fundamental Studies of Lithium-Sulfur Cell Chemistry Presentation given by...

  19. Neutron physics of the Re/Os clock. I. Measurement of the (n,gamma) cross sections of {sup 186,187,188}Os at the CERN n{sub T}OF facility

    SciTech Connect (OSTI)

    Mosconi, M.; Kaeppeler, F.; Audouin, L.; Dillmann, I.; Heil, M.; Plag, R.; Voss, F.; Walter, S.; Wisshak, K.; Fujii, K.; Abbondanno, U.; Belloni, F.; Milazzo, P. M.; Moreau, C.; Mengoni, A.; Domingo-Pardo, C.; Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.

    2010-07-15

    The precise determination of the neutron capture cross sections of {sup 186}Os and {sup 187}Os is important to define the s-process abundance of {sup 187}Os at the formation of the solar system. This quantity can be used to evaluate the radiogenic component of the abundance of {sup 187}Os due to the decay of the unstable {sup 187}Re (t{sub 1/2}=41.2 Gyr) and from this to infer the time duration of the nucleosynthesis in our galaxy (Re/Os cosmochronometer). The neutron capture cross sections of {sup 186}Os, {sup 187}Os, and {sup 188}Os have been measured at the CERN n{sub T}OF facility from 1 eV to 1 MeV, covering the entire energy range of astrophysical interest. The measurement has been performed by time-of-flight technique using isotopically enriched samples and two C{sub 6}D{sub 6} scintillation detectors for recording the prompt gamma rays emitted in the capture events. Maxwellian averaged capture cross sections have been determined for thermal energies between kT=5 and 100 keV corresponding to all possible s-process scenarios. The estimated uncertainties for the values at 30 keV are 4.1, 3.3, and 4.7% for {sup 186}Os, {sup 187}Os, and {sup 188}Os, respectively.

  20. Neutron and Nuclear Science Publications

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

    Publications Recent publications related to neutron and nuclear science at LANSCE. Neutron and Nuclear Science Publications Chi-Nu Publications DANCE Publications GEANIE Publications ICE House and ICE II Publications (n,z) Publications Neutron Radiography Publications SPIDER Publications Target 2 Publications TPC Publications Links Publications/Media Neutron and Nuclear Science News Profiles Events at LANSCE LANL Research Libary

  1. Neutron and Nuclear Science News

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

    News Recent news and events related to neutron and nuclear science at LANSCE. Neutron and Nuclear Science News Nuclear and Materials Science Research at LANSCE Nuclear science observations and opportunities at the Los Alamos Neutron Science Center Links Neutron and Nuclear Science News Media Links Profiles Events at LANSCE LAPIS (LANSCE Proposal Intake System

  2. Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

    SciTech Connect (OSTI)

    Grammer, K. B.; Alarcon, R.; Barrn-Palos, L.; Blyth, D.; Bowman, J. D.; Calarco, J.; Crawford, C.; Craycraft, K.; Evans, D.; Fomin, N.; Fry, J.; Gericke, M.; Gillis, R. C.; Greene, G. L.; Hamblen, J.; Hayes, C.; Kucuker, S.; Mahurin, R.; Maldonado-Velzquez, M.; Martin, E.; McCrea, M.; Mueller, P. E.; Musgrave, M.; Nann, H.; Penttil, S. I.; Snow, W. M.; Tang, Z.; Wilburn, W. S.

    2015-05-08

    Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section d?/d? from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also a widely used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. Furthermore, we describe our measurements and compare them with previous work.

  3. Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

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

    Grammer, K. B.; Alarcon, R.; Barrón-Palos, L.; Blyth, D.; Bowman, J. D.; Calarco, J.; Crawford, C.; Craycraft, K.; Evans, D.; Fomin, N.; et al

    2015-05-08

    Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσ/dΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component)more » using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also a widely used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. Furthermore, we describe our measurements and compare them with previous work.« less

  4. Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

    SciTech Connect (OSTI)

    Grammer, K. B.; Alarcon, R.; Barrón-Palos, L.; Blyth, D.; Bowman, J. D.; Calarco, J.; Crawford, C.; Craycraft, K.; Evans, D.; Fomin, N.; Fry, J.; Gericke, M.; Gillis, R. C.; Greene, G. L.; Hamblen, J.; Hayes, C.; Kucuker, S.; Mahurin, R.; Maldonado-Velázquez, M.; Martin, E.; McCrea, M.; Mueller, P. E.; Musgrave, M.; Nann, H.; Penttilä, S. I.; Snow, W. M.; Tang, Z.; Wilburn, W. S.

    2015-05-08

    Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσ/dΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also a widely used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. Furthermore, we describe our measurements and compare them with previous work.

  5. Fundamental Challenges in Solar to Fuel Conversion

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

    Ager, NERSC, 2/4/14 - 1 Fundamental Challenges in Solar to Fuel Conversion aka Improving on Photosynthesis Joel Ager Joint Center for Artificial Photosynthesis Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA February 4, 2014 NERSC User Meeting Berkeley, CA The Joint Center for Artificial Photosynthesis is a DOE Energy Innovation Hub, supported by the Office of Science of the U.S. Department of Energy Ager, NERSC, 2/4/14 - 2 What is "artificial

  6. DOE fundamentals handbook: Material science. Volume 1

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Mechanical Science Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of mechanical components and mechanical science. The handbook includes information on diesel engines, heat exchangers, pumps, valves, and miscellaneous mechanical components. This information will provide personnel with a foundation for understanding the construction and operation of mechanical components that are associated with various DOE nuclear facility operations and maintenance.

  7. DOE fundamentals handbook: Mechanical science. Volume 2

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Mechanical Science Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of mechanical components and mechanical science. The handbook includes information diesel engines, heat exchangers, pumps, valves, and miscellaneous mechanical components. This information will provide personnel with a foundation for understanding the construction and operation of mechanical components that are associated with various DOE nuclear facility operations and maintenance.

  8. EPICS V4 Evaluation for SNS Neutron Data

    SciTech Connect (OSTI)

    Kasemir, Kay; Pearson, Matthew R; Guyotte, Greg S

    2015-01-01

    Version 4 of the Experimental Physics and Industrial Control System (EPICS) toolkit allows defining application-specific structured data types (pvData) and offers a network protocol for their efficient exchange (pvAccess). We evaluated V4 for the transport of neutron events from the detectors of the Spallation Neutron Source (SNS) to data acquisition and experiment monitoring systems. This includes the comparison of possible data structures, performance tests, and experience using V4 in production on a beam line.

  9. Majewski named Fellow of the Neutron Scattering Society of America

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

    Majewski named Fellow of the Neutron Scattering Society of America Majewski named Fellow of the Neutron Scattering Society of America The Society recognized Majewski for "contributions to our understanding of weakly organized two-dimensional systems, including surfactant molecules found in biological systems." May 9, 2016 Jaroslaw (Jarek) Majewski Jaroslaw (Jarek) Majewski Communications Office (505) 667-7000 The American Physical Society named him as Fellow for his contributions to

  10. FABRICATION OF NEUTRON SOURCES

    DOE Patents [OSTI]

    Birden, J.H.

    1959-04-21

    A method is presented for preparing a neutron source from polonium-210 and substances, such as beryllium and boron, characterized by emission of neutrons upon exposure to alpha particles from the polonium. According to the invention, a source is prepared by placing powdered beryllium and a platinum foil electroplated with polonium-2;.0 in a beryllium container. The container is sealed and then heated by induction to a temperature of 450 to 1100 deg C to volatilize the polonium off the foil into the powder. The heating step is terminated upon detection of a maximum in the neutron flux level.

  11. Neutron emission profiles and energy spectra measurements at JET

    SciTech Connect (OSTI)

    Giacomelli, L.; Conroy, S.; Belli, F.; Riva, M.; Gorini, G.; Horton, L.; Joffrin, E.; Lerche, E.; Murari, A.; Popovichev, S.; Syme, B.; Collaboration: JET EFDA Contributors

    2014-08-21

    The Joint European Toras (JET, Culham, UK) is the largest tokamak in the world. It is devoted to nuclear fusion experiments of magnetic confined Deuterium (D) or Deuterium-Tritium (DT) plasmas. JET has been upgraded over the years and recently it has also become a test facility of the components designed for ITER, the next step fusion machine under construction in Cadarache (France). JET makes use of many different diagnostics to measure the physical quantities of interest in plasma experiments. Concerning D or DT plasmas neutron production, various types of detectors are implemented to provide information upon the neutron total yield, emission profile and energy spectrum. The neutron emission profile emitted from the JET plasma poloidal section is reconstructed using the neutron camera (KN3). In 2010 KN3 was equipped with a new digital data acquisition system capable of high rate neutron measurements (<0.5 MCps). A similar instrument will be implemented on ITER and it is currently in its design phase. Various types of neutron spectrometers with different view lines are also operational on JET. One of them is a new compact spectrometer (KM12) based on organic liquid scintillating material which was installed in 2010 and implements a similar digital data acquisition system as for KN3. This article illustrates the measurement results of KN3 neutron emission profiles and KM 12 neutron energy spectra from the latest JET D experimental campaign C31.

  12. 2010 Neutron Review: ORNL Neutron Sciences Progress Report

    SciTech Connect (OSTI)

    Bardoel, Agatha A; Counce, Deborah M; Ekkebus, Allen E; Horak, Charlie M; Nagler, Stephen E; Kszos, Lynn A

    2011-06-01

    During 2010, the Neutron Sciences Directorate focused on producing world-class science, while supporting the needs of the scientific community. As the instrument, sample environment, and data analysis tools at High Flux Isotope Reactor (HFIR ) and Spallation Neutron Source (SNS) have grown over the last year, so has promising neutron scattering research. This was an exciting year in science, technology, and operations. Some topics discussed are: (1) HFIR and SNS Experiments Take Gordon Battelle Awards for Scientific Discovery - Battelle Memorial Institute presented the inaugural Gordon Battelle Prizes for scientific discovery and technology impact in 2010. Battelle awards the prizes to recognize the most significant advancements at national laboratories that it manages or co-manages. (2) Discovery of Element 117 - As part of an international team of scientists from Russia and the United States, HFIR staff played a pivotal role in the discovery by generating the berkelium used to produce the new element. A total of six atoms of ''ununseptium'' were detected in a two-year campaign employing HFIR and the Radiochemical Engineering Development Center at Oak Ridge National Laboratory (ORNL) and the heavy-ion accelerator capabilities at the Joint Institute for Nuclear Research in Dubna, Russia. The discovery of the new element expands the understanding of the properties of nuclei at extreme numbers of protons and neutrons. The production of a new element and observation of 11 new heaviest isotopes demonstrate the increased stability of super-heavy elements with increasing neutron numbers and provide the strongest evidence to date for the existence of an island of enhanced stability for super-heavy elements. (3) Studies of Iron-Based High-Temperature Superconductors - ORNL applied its distinctive capabilities in neutron scattering, chemistry, physics, and computation to detailed studies of the magnetic excitations of iron-based superconductors (iron pnictides and

  13. Schoenborn wins Bau Neutron Award

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

    Schoenborn wins Bau Neutron Award Schoenborn wins Bau Neutron Award The American Crystallographic Association (ACA) has selected retired Laboratory Senior Fellow Benno Schoenborn to receive the 2016 Bau Neutron Diffraction Award. August 12, 2015 Benno Schoenborn Benno Schoenborn Communications Office (505) 667-7000 Schoenborn is honored for his pioneering research in macromolecular neutron crystallography and the design and development of the neutron crystallography beamline (Protein

  14. Switchable radioactive neutron source device

    DOE Patents [OSTI]

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

    1987-11-06

    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. 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

    2014-03-04

    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.

  16. Neutron resonance averaging

    SciTech Connect (OSTI)

    Chrien, R.E.

    1986-10-01

    The principles of resonance averaging as applied to neutron capture reactions are described. Several illustrations of resonance averaging to problems of nuclear structure and the distribution of radiative strength in nuclei are provided. 30 refs., 12 figs.

  17. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2005-06-14

    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.

  18. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2008-04-22

    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.

  19. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2009-12-29

    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.

  20. Is there further evidence for spatial variation of fundamental constants?

    SciTech Connect (OSTI)

    Berengut, J. C.; Flambaum, V. V.; King, J. A.; Curran, S. J.; Webb, J. K.

    2011-06-15

    Indications of spatial variation of the fine-structure constant, {alpha}, based on study of quasar absorption systems have recently been reported [J. K. Webb, J. A. King, M. T. Murphy, V. V. Flambaum, R. F. Carswell, and M. B. Bainbridge, arXiv:1008.3907.]. The physics that causes this {alpha}-variation should have other observable manifestations, and this motivates us to look for complementary astrophysical effects. In this paper we propose a method to test whether spatial variation of fundamental constants existed during the epoch of big bang nucleosynthesis and study existing measurements of deuterium abundance for a signal. We also examine existing quasar absorption spectra data that are sensitive to variation of the electron-to-proton mass ratio {mu} and x={alpha}{sup 2{mu}}g{sub p} for spatial variation.

  1. FABRICATION OF NEUTRON SOURCES

    DOE Patents [OSTI]

    Birden, J.H.

    1959-01-20

    A method is presented for preparing a more efficient neutron source comprising inserting in a container a quantity of Po-210, inserting B powder coated with either Ag, Pt, or Ni. The container is sealed and then slowly heated to about 450 C to volatilize the Po and effect combination of the coated powder with the Po. The neutron flux emitted by the unit is moritored and the heating step is terminated when the flux reaches a maximum or selected level.

  2. NEUTRON FLUX INTENSITY DETECTION

    DOE Patents [OSTI]

    Russell, J.T.

    1964-04-21

    A method of measuring the instantaneous intensity of neutron flux in the core of a nuclear reactor is described. A target gas capable of being transmuted by neutron bombardment to a product having a resonance absorption line nt a particular microwave frequency is passed through the core of the reactor. Frequency-modulated microwave energy is passed through the target gas and the attenuation of the energy due to the formation of the transmuted product is measured. (AEC)

  3. Hydrogen Production: Fundamentals and Case Study Summaries (Presentation)

    SciTech Connect (OSTI)

    Harrison, K.; Remick, R.; Hoskin, A.; Martin, G.

    2010-05-19

    This presentation summarizes hydrogen production fundamentals and case studies, including hydrogen to wind case studies.

  4. Physicist (Fundamental Symmetries) | Department of Energy

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

    Germantown, Maryland Announcement Number 16-DE-SC-HQ-007 Job Summary The Office of Science is the single largest supporter of basic research in the physical sciences in the...

  5. Fundamental bioprocessing research for coal applications

    SciTech Connect (OSTI)

    Kaufman, E.N.

    1996-06-01

    The purpose of this program is to gain a fundamental understanding and sound scientific technical basis for evaluating the potential roles of innovative bioprocessing concepts for the utilization and conversion of coal. The aim is to explore the numerous ways in which advanced biological processes and techniques can open new opportunities for coal utilization or can replace more conventional techniques by use of milder conditions with less energy consumption or loss. There are several roles where biotechnology is likely to be important in coal utilization and conversion. These include potential bioprocessing systems such.

  6. DOE fundamentals handbook: Chemistry. Volume 1

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Chemistry Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of chemistry. The handbook includes information on the atomic structure of matter; chemical bonding; chemical equations; chemical interactions involved with corrosion processes; water chemistry control, including the principles of water treatment; the hazards of chemicals and gases, and basic gaseous diffusion processes. This information will provide personnel with a foundation for understanding the chemical properties of materials and the way these properties can impose limitations on the operation of equipment and systems.

  7. DOE fundamentals handbook: Chemistry. Volume 2

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    This handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of chemistry. This volume contains the following modules: reactor water chemistry (effects of radiation on water chemistry, chemistry parameters), principles of water treatment (purpose; treatment processes [ion exchange]; dissolved gases, suspended solids, and pH control; water purity), and hazards of chemicals and gases (corrosives [acids, alkalies], toxic compounds, compressed gases, flammable/combustible liquids).

  8. Microwaves and particle accelerators: a fundamental link

    SciTech Connect (OSTI)

    Chattopadhyay, Swapan

    2011-07-01

    John Cockcroft's splitting of the atom and Ernest Lawrence's invention of the cyclotron in the first half of the twentieth century ushered in the grand era of ever higher energy particle accelerators to probe deeper into matter. It also forged a link, bonding scientific discovery with technological innovation that continues today in the twenty first century. The development of radar and high power vacuum electronics, especially microwave power tubes like the magnetrons and the klystrons in the pre-second world war era, was instrumental in the rapid development of circular and linear charged particle accelerators in the second half of the twentieth century. We had harnessed the powerful microwave radio-frequency sources from few tens of MHz to up to 90 GHz spanning L-band to W-band frequencies. Simultaneously in the second half of the twentieth century, lasers began to offer very first opportunities of controlling charged particles at smaller resolutions on the scale of wavelengths of visible light. We also witnessed in this period the emergence of the photon and neutron sciences driven by accelerators built-by-design producing tailored and ultra-bright pulses of bright photons and neutrons to probe structure and function of matter from aggregate to individual molecular and atomic scales in unexplored territories in material and life sciences. As we enter the twenty first century, the race for ever higher energies, brightness and luminosity to probe atto-metric and atto-second domains of the ultra-small structures and ultra-fast processes continues. These developments depend crucially on yet further advancements in the production and control of high power and high frequency microwaves and light sources, often intricately coupled in their operation to the high energy beams themselves. We give a glimpse of the recent developments and innovations in the electromagnetic production and control of charged particle beams in the service of science and society. (author)

  9. Toms Arias > ProfessorDepartment of Physics > Faculty Directory...

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

    systems including carbon nanotubes, fundamental processes involved in crystal growth, quantum mechanics of systems in contact with a solution, physics of novel solar cell...

  10. PHYSICAL SCIENCES, Physics Phase

    Office of Scientific and Technical Information (OSTI)

    SCIENCES, Physics Phase competition in trisected superconducting dome I. M. Vishik, 1, 2 M Hashimoto, 3 R.-H. He, 4 W. S. Lee, 1, 2 F. Schmitt, 1, 2 D. H. Lu, 3 R. G. Moore, 1...

  11. 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)

    2013-11-15

    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.

  12. Inquiring Minds - Questions About Physics

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

    Is Antineutron the Same as Neutron? You Wrote: My name is Killian Lobato. I am a year 13 IB student in St. Julians Portugal. I have come across in my physics book the idea of anti matter. Anti matter is the same as its opposing matter but has an opposite charge. Now as the nuetron has no charge what makes its anti particle different. The idea i have is that the Anti Neutron is the fussion of an anti proton and an anti electron (a positron, i do not know the anti particle of proton). Hello

  13. Inquiring Minds - Questions About Physics

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

    You Wrote: Hi my question is what is the number of atoms in the world and why don't scientist agree on one number for them. Thank you. Hi, the answer to your question by its very nature can not be terribly accurate. However, when I pull down my copy of a college physics book, I find that it lists the mass of the earth as (6 x 10^24 kg). The mass of a proton or neutron is (1.67 x 10^-27 kg). Consequently, you can say to mediocre accuracy that the number of protons or neutrons in the earth is

  14. Neutron Detection Using an Embedded Sol-Gel Neutron Absorber...

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

    Date Patent 5,973,328 Patent 5,973,328 Neutron detector using sol-gel absorber An neutron detector composed of fissionable material having ions of lithium, uranium, thorium, ...

  15. Category:Neutron Log | Open Energy Information

    Open Energy Info (EERE)

    Looking for the Neutron Log page? For detailed information on Neutron Log, click here. Category:Neutron Log Add.png Add a new Neutron Log Technique Pages in category...

  16. Nuclear Physics Review

    SciTech Connect (OSTI)

    Walker-Loud, Andre

    2014-11-01

    Anchoring low-energy nuclear physics to the fundamental theory of strong interactions remains an outstanding challenge. I review the current progress and challenges of the endeavor to use lattice QCD to bridge this connection. This is a particularly exciting time for this line of research as demonstrated by the spike in the number of different collaborative efforts focussed on this problem and presented at this conference. I first digress and discuss the 2013 Ken Wilson Award.

  17. Portable Neutron Sensors for Emergency Response Operations

    SciTech Connect (OSTI)

    Mukhopadhyay, S., Maurer, R., Detweiler, R.

    2012-06-22

    This slide-show presents neutron measurement work, including design, use and performance of different neutron detection systems.

  18. Physics validation studies for muon collider detector background simulations

    SciTech Connect (OSTI)

    Morris, Aaron Owen; /Northern Illinois U.

    2011-07-01

    Within the broad discipline of physics, the study of the fundamental forces of nature and the most basic constituents of the universe belongs to the field of particle physics. While frequently referred to as 'high-energy physics,' or by the acronym 'HEP,' particle physics is not driven just by the quest for ever-greater energies in particle accelerators. Rather, particle physics is seen as having three distinct areas of focus: the cosmic, intensity, and energy frontiers. These three frontiers all provide different, but complementary, views of the basic building blocks of the universe. Currently, the energy frontier is the realm of hadron colliders like the Tevatron at Fermi National Accelerator Laboratory (Fermilab) or the Large Hadron Collider (LHC) at CERN. While the LHC is expected to be adequate for explorations up to 14 TeV for the next decade, the long development lead time for modern colliders necessitates research and development efforts in the present for the next generation of colliders. This paper focuses on one such next-generation machine: a muon collider. Specifically, this paper focuses on Monte Carlo simulations of beam-induced backgrounds vis-a-vis detector region contamination. Initial validation studies of a few muon collider physics background processes using G4beamline have been undertaken and results presented. While these investigations have revealed a number of hurdles to getting G4beamline up to the level of more established simulation suites, such as MARS, the close communication between us, as users, and the G4beamline developer, Tom Roberts, has allowed for rapid implementation of user-desired features. The main example of user-desired feature implementation, as it applies to this project, is Bethe-Heitler muon production. Regarding the neutron interaction issues, we continue to study the specifics of how GEANT4 implements nuclear interactions. The GEANT4 collaboration has been contacted regarding the minor discrepancies in the neutron

  19. Neutron stars' X-ray superbursts mystify, inspire Los Alamos scientists

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

    Neutron stars' X-ray superbursts mystify, inspire Neutron stars' X-ray superbursts mystify, inspire Los Alamos scientists Massive X-ray superbursts near the surface of neutron stars are providing a unique window into the operation of fundamental forces of nature under extreme conditions. December 6, 2013 A small, dense object only 12 miles in diameter is responsible for this beautiful X-ray nebula that spans 150 light years. At the center of this image made by NASA's Chandra X-ray Observatory is

  20. Search for the Neutron Electric Dipole Moment at the SNS at Oak Ridge

    SciTech Connect (OSTI)

    Kolarkar, Ameya

    2010-02-10

    The possible existence of a non-zero electric dipole moment (EDM) of the neutron is of fundamental interest for our understanding of the nature of electro-weak and strong interactions. The experimental search for this moment has the potential to reveal new sources of T and CP violation and to challenge calculations that propose extensions to the Standard Model. A new experiment being developed at the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory seeks to lower the current EDM limit of the neutron by a factor of 50 to 100 over the present upper limit of 2.9x10{sup -26} e cm.

  1. Fundamentals of fluidized bed chemical processes

    SciTech Connect (OSTI)

    Yates, J.G.

    1983-01-01

    Chemical processes based on the use of fluidized solids, although widely used on an industrial scale for some four decades, are currently increasing in importance as industry looks for improved methods for handling and reacting solid materials. This book provides background necessary for an understanding of the technique of gas-solid fluidization. Contents: Some Fundamental Aspects of Fluidization-General Features of Gas-Solid Fluidization; Minimum Fluidization Velocity; Inter-particle forces; Liquid-Solid Fluidization; Bubbles; Slugging; Entrainment and Elutriation; Particle Movement; Bed Viscosity; Fluidization Under Pressure. Fluidized-Bed Reactor Models-ome Individual Models; Model Comparisons; Multiple Region Models. Catalytic Cracking-Process Developments Riser Cracking; Catalysis; Process Chemistry; Kinetics; Process Models. Combustion and Gasification-Plant Developments; Oil and Gas Combustion; Desulphurization; No/sub x/ Emissions; Coal Gassification. Miscellaneous Processes-Phthalic Anhydride (1,3-isobezofurandione); Acrylonitrile (prop-3-enenitrile); Vinyl Chloride (chloroethene); Titanium Dioxide; Uranium Processing; Sulphide Roasting; Indexes.

  2. Neutronic reactor construction

    DOE Patents [OSTI]

    Huston, Norman E.

    1976-07-06

    1. A neutronic reactor comprising a moderator including horizontal layers formed of horizontal rows of graphite blocks, alternate layers of blocks having the rows extending in one direction, the remaining alternate layers having the rows extending transversely to the said one direction, alternate rows of blocks in one set of alternate layers having longitudinal ducts, the moderator further including slotted graphite tubes positioned in the ducts, the reactor further comprising an aluminum coolant tube positioned within the slotted tube in spaced relation thereto, bodies of thermal-neutron-fissionable material, and jackets enclosing the bodies and being formed of a corrosion-resistant material having a low neutron-capture cross section, the bodies and jackets being positioned within the coolant tube so that the jackets are spaced from the coolant tube.

  3. Spherical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2006-11-21

    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.

  4. Personnel electronic neutron dosimeter

    DOE Patents [OSTI]

    Falk, Roger B.; Tyree, William H.

    1984-12-18

    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.

    1982-03-03

    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. METHOD OF PRODUCING NEUTRONS

    DOE Patents [OSTI]

    Imhoff, D.H.; Harker, W.H.

    1964-02-01

    A method for producing neutrons is described in which there is employed a confinement zone defined between longitudinally spaced localized gradient regions of an elongated magnetic field. Changed particles and neutralizing electrons, more specifically deuterons and tritons and neutralizng electrons, are injected into the confinement field from ion sources located outside the field. The rotational energy of the parrticles is increased at the gradients by imposing an oscillating transverse electrical field thereacross. The imposition of such oscillating transverse electrical fields improves the reflection capability of such gradient fielda so that the reactive particles are retained more effectively within the zone. With the attainment of appropriate densities of plasma particles and provided that such particles are at a sufficiently high temperature, neutron-producing reactions ensue and large quantities of neutrons emerge from the containment zone. (AEC)

  7. Ultrafast neutron detector

    DOE Patents [OSTI]

    Wang, Ching L.

    1987-01-01

    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.

  8. Neutron Log | Open Energy Information

    Open Energy Info (EERE)

    Dictionary.png Neutron Log: The neutron log responds primarily to the amount of hydrogen in the formation which is contained in oil, natural gas, and water. The amount of...

  9. Combinatorial evaluation of systems including decomposition of a system representation into fundamental cycles

    DOE Patents [OSTI]

    Oliveira, Joseph S.; Jones-Oliveira, Janet B.; Bailey, Colin G.; Gull, Dean W.

    2008-07-01

    One embodiment of the present invention includes a computer operable to represent a physical system with a graphical data structure corresponding to a matroid. The graphical data structure corresponds to a number of vertices and a number of edges that each correspond to two of the vertices. The computer is further operable to define a closed pathway arrangement with the graphical data structure and identify each different one of a number of fundamental cycles by evaluating a different respective one of the edges with a spanning tree representation. The fundamental cycles each include three or more of the vertices.

  10. Conjunction of Multizone Infiltration Specialists (COMIS) fundamentals

    SciTech Connect (OSTI)

    Feustel, H.E.; Rayner-Hooson, A.

    1990-05-01

    The COMIS workshop (Conjunction of Multizone Infiltration Specialists) was a joint research effort to develop a multizone infiltration mode. This workshop (October 1988--September 1989) was hosted by the Energy Performance of Buildings Group at Lawrence Berkeley Laboratory's Applied Science Division. The task of the workshop was to develop a detailed multizone infiltration program taking crack flow, HVAC-systems, single-sided ventilation and transport mechanism through large openings into account. This work was accomplished not by investigating into numerical description of physical phenomena but by reviewing the literature for the best suitable algorithm. The numerical description of physical phenomena is clearly a task of IEA-Annex XX Air Flow Patterns in Buildings,'' which will be finished in September 1991. Multigas tracer measurements and wind tunnel data will be used to check the model. The agenda integrated all participants' contributions into a single model containing a large library of modules. The user-friendly program is aimed at researchers and building professionals. From its announcement in December 1986, COMIS was well received by the research community. Due to the internationality of the group, several national and international research programmes were co-ordinated with the COMIS workshop. Colleagues for France, Italy, Japan, The Netherlands, People's Republic of China, Spain, Sweden, Switzerland, and the United States of America were working together on the development of the model. Even though this kind of co-operation is well known in other fields of research, e.g., high energy physics; for the field of building physics it is a new approach. This document contains an overview about infiltration modelling as well as the physics and the mathematics behind the COMIS model. 91 refs., 38 figs., 9 tabs.

  11. Neutron and gamma irradiation damage to organic materials.

    SciTech Connect (OSTI)

    White, Gregory Von, II; Bernstein, Robert

    2012-04-01

    This document discusses open literature reports which investigate the damage effects of neutron and gamma irradiation on polymers and/or epoxies - damage refers to reduced physical chemical, and electrical properties. Based on the literature, correlations are made for an SNL developed epoxy (Epon 828-1031/DDS) with an expected total fast-neutron fluence of {approx}10{sup 12} n/cm{sup 2} and a {gamma} dosage of {approx}500 Gy received over {approx}30 years at < 200 C. In short, there are no gamma and neutron irradiation concerns for Epon 828-1031/DDS. To enhance the fidelity of our hypotheses, in regards to radiation damage, we propose future work consisting of simultaneous thermal/irradiation (neutron and gamma) experiments that will help elucidate any damage concerns at these specified environmental conditions.

  12. 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

    2012-05-29

    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.

  13. 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

    2013-11-12

    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.

  14. GUIDE FOR POLARIZED NEUTRONS

    DOE Patents [OSTI]

    Sailor, V.L.; Aichroth, R.W.

    1962-12-01

    The plane of polarization of a beam of polarized neutrons is changed by this invention, and the plane can be flipped back and forth quicitly in two directions in a trouble-free manner. The invention comprises a guide having a plurality of oppositely directed magnets forming a gap for the neutron beam and the gaps are spaced longitudinally in a spiral along the beam at small stepped angles. When it is desired to flip the plane of polarization the magnets are suitably rotated to change the direction of the spiral of the gaps. (AEC)

  15. NEUTRONIC REACTOR CONTROL ELEMENT

    DOE Patents [OSTI]

    Newson, H.W.

    1960-09-13

    A novel composite neutronic reactor control element is offered. The element comprises a multiplicity of sections arranged in end-to-end relationship, each of the sections having a markedly different neutron-reactive characteristic. For example, a three-section control element could contain absorber, moderator, and fuel sections. By moving such an element longitudinally through a reactor core, reactivity is decreased by the absorber, increased slightly by the moderator, or increased substantially by the fuel. Thus, control over a wide reactivity range is provided.

  16. Simplified fast neutron dosimeter

    DOE Patents [OSTI]

    Sohrabi, Mehdi

    1979-01-01

    Direct fast-neutron-induced recoil and alpha particle tracks in polycarbonate films may be enlarged for direct visual observation and automated counting procedures employing electrochemical etching techniques. Electrochemical etching is, for example, carried out in a 28% KOH solution at room temperature by applying a 2000 V peak-to-peak voltage at 1 kHz frequency. Such recoil particle amplification can be used for the detection of wide neutron dose ranges from 1 mrad. to 1000 rads. or higher, if desired.

  17. FAST NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Snell, A.H.

    1957-12-01

    This patent relates to a reactor and process for carrying out a controlled fast neutron chain reaction. A cubical reactive mass, weighing at least 920 metric tons, of uranium metal containing predominantly U/sup 238/ and having a U/sup 235/ content of at least 7.63% is assembled and the maximum neutron reproduction ratio is limited to not substantially over 1.01 by insertion and removal of a varying amount of boron, the reactive mass being substantially freed of moderator.

  18. Neutron activated switch

    DOE Patents [OSTI]

    Barton, David M.

    1991-01-01

    A switch for reacting quickly to a neutron emission. A rod consisting of fissionable material is located inside a vacuum tight body. An adjustable contact is located coaxially at an adjustable distance from one end of the rod. Electrical leads are connected to the rod and to the adjustable contact. With a vacuum drawn inside the body, a neutron bombardment striking the rod causes it to heat and expand longitudinally until it comes into contact with the adjustable contact. This circuit closing occurs within a period of a few microseconds.

  19. Muon Physics in the 21st Century

    SciTech Connect (OSTI)

    Marciano, Bill

    2005-05-11

    Intense muon sources have great potential in fundamental physics and applied science. An overview of future possibilities ranging from muon-electron conversion to muon catalyzed fusion and medical diagnostics will be given.

  20. Physics Nobel winner David Gross gives public lecture at Jefferson...

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

    Nobel winner David Gross gives public lecture at Jefferson Lab on June 12 (Monday) Physics ... "The Coming Revolutions in Fundamental Physics" beginning at 8 p.m. at Jefferson Lab on ...

  1. The Particle Physics of You | Department of Energy

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

    The Particle Physics of You The Particle Physics of You November 6, 2015 - 2:12pm Addthis Not only are we made of fundamental particles, we also produce them and are constantly...

  2. Nuclear Physics and the New Standard Model

    SciTech Connect (OSTI)

    Ramsey-Musolf, Michael J. [Department of Physics, University of Wisconsin-Madison, Madison, WI 53706 (United States) and Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States)

    2010-08-04

    Nuclear physics studies of fundamental symmetries and neutrino properties have played a vital role in the development and confirmation of the Standard Model of fundamental interactions. With the advent of the CERN Large Hadron Collider, experiments at the high energy frontier promise exciting discoveries about the larger framework in which the Standard Model lies. In this talk, I discuss the complementary opportunities for probing the 'new Standard Model' with nuclear physics experiments at the low-energy high precision frontier.

  3. Neutron matter with Quantum Monte Carlo: chiral 3N forces and static response

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

    Buraczynski, M.; Gandolfi, S.; Gezerlis, A.; Schwenk, A.; Tews, I.

    2016-03-01

    Neutron matter is related to the physics of neutron stars and that of neutron-rich nuclei. Moreover, Quantum Monte Carlo (QMC) methods offer a unique way of solving the many-body problem non-perturbatively, providing feedback on features of nuclear interactions and addressing scenarios that are inaccessible to other approaches. Our contribution goes over two recent accomplishments in the theory of neutron matter: a) the fusing of QMC with chiral effective field theory interactions, focusing on local chiral 3N forces, and b) the first attempt to find an ab initio solution to the problem of static response.

  4. Single crystal neutron diffraction study of lattice and magnetic structures of 5M modulated Ni2Mn1.14Ga0.86

    SciTech Connect (OSTI)

    Pramanick, Abhijit; Wang, Xiaoping; An, Ke; Stoica, Alexandru Dan; Hoffmann, Christina; Wang, Xun-Li

    2012-01-01

    A comprehensive description of the crystal and magnetic structures of Ni-Mn-Ga magnetic shape memory alloys is important to understand the physical origins of their magnetoelastic properties. These structural details for an off-stoichiometric Ni2Mn1.14Ga0.86 alloy have been obtained from refinement of high-resolution single crystal neutron diffraction data following a (3+1)-dimensional superspace formalism. In particular, the structure adopts a P2/m( 0 )00 (3+1)-D superspace symmetry with the following fundamental lattice parameters: a=4.255(4) , b=5.613(4) , c=4.216(3) , a commensurate periodicity of 5M and a modulation wave vector of . The magnetic moments are aligned along the b-axis. The modulations for atomic site displacements, site occupancies and magnetic moments are elucidated from a (3+1)-D refinement of the neutron diffraction data. In addition to atomic displacements corresponding to shear waves along <110>, distortions of Ni-centric tetrahedra are also evident. Physical interpretations for the different structural distortions and their relationship with magnetic properties are discussed.

  5. Neutron Absorbing Alloys

    DOE Patents [OSTI]

    Mizia, Ronald E.; Shaber, Eric L.; DuPont, John N.; Robino, Charles V.; Williams, David B.

    2004-05-04

    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.

  6. NEUTRONIC REACTOR SHIELDING

    DOE Patents [OSTI]

    Borst, L.B.

    1961-07-11

    A special hydrogenous concrete shielding for reactors is described. In addition to Portland cement and water, the concrete essentially comprises 30 to 60% by weight barytes aggregate for enhanced attenuation of fast neutrons. The biological shields of AEC's Oak Ridge Graphite Reactor and Materials Testing Reactor are particular embodiments.

  7. NEUTRONIC REACTOR CONTROL ELEMENT

    DOE Patents [OSTI]

    Beaver, R.J.; Leitten, C.F. Jr.

    1962-04-17

    A boron-10 containing reactor control element wherein the boron-10 is dispersed in a matrix material is describeri. The concentration of boron-10 in the matrix varies transversely across the element from a minimum at the surface to a maximum at the center of the element, prior to exposure to neutrons. (AEC)

  8. Neutronic reactor thermal shield

    DOE Patents [OSTI]

    Wende, Charles W. J.

    1976-06-15

    1. The method of operating a water-cooled neutronic reactor having a graphite moderator which comprises flowing a gaseous mixture of carbon dioxide and helium, in which the helium comprises 40-60 volume percent of the mixture, in contact with the graphite moderator.

  9. NEUTRONIC REACTOR STRUCTURE

    DOE Patents [OSTI]

    Weinberg, A.M.; Vernon, H.C.

    1961-05-30

    A neutronic reactor is described. It has a core consisting of natural uranium and heavy water and having a K-factor greater than unity which is surrounded by a reflector consisting of natural uranium and ordinary water having a Kfactor less than unity.

  10. Neutronic Reactor Structure

    DOE Patents [OSTI]

    Vernon, H. C.; Weinberg, A. M.

    1961-05-30

    The neutronic reactor is comprised of a core consisting of natural uranium and heavy water with a K-factor greater than unity. The core is surrounded by a reflector consisting of natural uranium and ordinary water with a Kfactor less than unity. (AEC)

  11. Fundamental Scientific Problems in Magnetic Recording

    SciTech Connect (OSTI)

    Schulthess, T.C.; Miller, M.K.

    2007-06-27

    Magnetic data storage technology is presently leading the high tech industry in advancing device integration--doubling the storage density every 12 months. To continue these advancements and to achieve terra bit per inch squared recording densities, new approaches to store and access data will be needed in about 3-5 years. In this project, collaboration between Oak Ridge National Laboratory (ORNL), Center for Materials for Information Technology (MINT) at University of Alabama (UA), Imago Scientific Instruments, and Seagate Technologies, was undertaken to address the fundamental scientific problems confronted by the industry in meeting the upcoming challenges. The areas that were the focus of this study were to: (1) develop atom probe tomography for atomic scale imaging of magnetic heterostructures used in magnetic data storage technology; (2) develop a first principles based tools for the study of exchange bias aimed at finding new anti-ferromagnetic materials to reduce the thickness of the pinning layer in the read head; (3) develop high moment magnetic materials and tools to study magnetic switching in nanostructures aimed at developing improved writers of high anisotropy magnetic storage media.

  12. Dose-equivalent neutron dosimeter

    DOE Patents [OSTI]

    Griffith, R.V.; Hankins, D.E.; Tomasino, L.; Gomaa, M.A.M.

    1981-01-07

    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.

  13. The Brief Lives of Neutrons

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

    The Brief Lives of Neutrons 1663 Los Alamos science and technology magazine Latest Issue:July 2016 past issues All Issues » submit The Brief Lives of Neutrons A unique experiment to pin down the neutron's surprisingly elusive half-life July 21, 2016 Most neutrons inside atoms are stable. But get one on its own, and it will disintegrate in about ten minutes. Most neutrons inside atoms are stable. But get one on its own, and it will disintegrate in about ten minutes. Beam and bottle experiments

  14. 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)

    1999-01-01

    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.

  15. 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.

    1999-08-17

    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.

  16. A poloidal section neutron camera for MAST upgrade

    SciTech Connect (OSTI)

    Sangaroon, S.; Weiszflog, M.; Cecconello, M.; Conroy, S.; Ericsson, G.; Wodniak, I.; Keeling, D.; Turnyanskiy, M. [EURATOM Collaboration: MAST Team

    2014-08-21

    The Mega Ampere Spherical Tokamak Upgrade (MAST Upgrade) is intended as a demonstration of the physics viability of the Spherical Tokamak (ST) concept and as a platform for contributing to ITER/DEMO physics. Concerning physics exploitation, MAST Upgrade plasma scenarios can contribute to the ITER Tokamak physics particularly in the field of fast particle behavior and current drive studies. At present, MAST is equipped with a prototype neutron camera (NC). On the basis of the experience and results from previous experimental campaigns using the NC, the conceptual design of a neutron camera upgrade (NC Upgrade) is being developed. As part of the MAST Upgrade, the NC Upgrade is considered a high priority diagnostic since it would allow studies in the field of fast ions and current drive with good temporal and spatial resolution. In this paper, we explore an optional design with the camera array viewing the poloidal section of the plasma from different directions.

  17. Call issued for Lujan Neutron Scattering Center proposals

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

    (polarized and unpolarized) Inelastic neutron scattering spectroscopy Small angle neutron scattering Neutron radiographytomography The Lujan instruments webpage...

  18. Coated Fiber Neutron Detector Test

    SciTech Connect (OSTI)

    Lintereur, Azaree T.; Ely, James H.; Kouzes, Richard T.; Stromswold, David C.

    2009-10-23

    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).

  19. [Fundamental studies of passivity and passivity breakdown

    SciTech Connect (OSTI)

    Macdonald, D.D.

    1993-07-01

    We developed and experimentally tested physical models for growth and breakdown of passive films on metal surfaces. These models are ``point defect models,`` in which the growth and breakdown are described in terms of movement of anion and cation vacancies. The work during the past 5 years resulted in: theory of growth and breakdown of passive films, theory of corrosion-resistant alloys, electronic structure of passive films, and estimation of damage functions for energy systems. Proposals are give for the five ongoing tasks. 10 figs.

  20. Materials Physics | Materials Science | NREL

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

    Physics A photo of laser light rays going in various directions atop a corrugated metal substrate In materials physics, NREL focuses on realizing materials that transcend the present constraints of photovoltaic (PV) and solid-state lighting technologies. Through materials growth and characterization, coupled with theoretical modeling, we seek to understand and control fundamental electronic and optical processes in semiconductors. Capabilities Optimizing New Materials An illustration showing

  1. Fast-neutron coded-aperture imaging of special nuclear material configurations

    SciTech Connect (OSTI)

    P. A. Hausladen; M. A. Blackston; E. Brubaker; D. L. Chichester; P. Marleau; R. J. Newby

    2012-07-01

    In the past year, a prototype fast-neutron coded-aperture imager has been developed that has sufficient efficiency and resolution to make the counting of warheads for possible future treaty confirmation scenarios via their fission-neutron emissions practical. The imager is constructed from custom-built pixelated liquid scintillator detectors. The liquid scintillator detectors enable neutron-gamma discrimination via pulse shape, and the pixelated construction enables a sufficient number of pixels for imaging in a compact detector with a manageable number of channels of readout electronics. The imager has been used to image neutron sources at ORNL, special nuclear material (SNM) sources at the Idaho National Laboratory (INL) Zero Power Physics Reactor (ZPPR) facility, and neutron source and shielding configurations at Sandia National Laboratories. This paper reports on the design and construction of the imager, characterization measurements with neutron sources at ORNL, and measurements with SNM at the INL ZPPR facility.

  2. Physics Fellow

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

    as Institute of Physics Fellow January 18, 2011 LOS ALAMOS, New Mexico, January 18, ... simulation, and computation, has been selected as a Fellow of the Institute of Physics. ...

  3. Nuclear Physics

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

    Nuclear Physics Nuclear Physics Enabling remarkable discoveries and tools that transform our understanding of energy and matter and advance national, economic, and energy security. ...

  4. Theoretical Physics

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

    HEP Theoretical Physics Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get ... HEP Theory at Los Alamos The Theoretical High Energy Physics group at ...

  5. Prospects for measuring neutron-star masses and radii with X-ray pulse profile modeling

    SciTech Connect (OSTI)

    Psaltis, Dimitrios; Özel, Feryal; Chakrabarty, Deepto E-mail: fozel@email.arizona.edu

    2014-06-01

    Modeling the amplitudes and shapes of the X-ray pulsations observed from hot, rotating neutron stars provides a direct method for measuring neutron-star properties. This technique constitutes an important part of the science case for the forthcoming NICER and proposed LOFT X-ray missions. In this paper, we determine the number of distinct observables that can be derived from pulse profile modeling and show that using only bolometric pulse profiles is insufficient for breaking the degeneracy between inferred neutron-star radius and mass. However, we also show that for moderately spinning (300-800 Hz) neutron stars, analysis of pulse profiles in two different energy bands provides additional constraints that allow a unique determination of the neutron-star properties. Using the fractional amplitudes of the fundamental and the second harmonic of the pulse profile in addition to the amplitude and phase difference of the spectral color oscillations, we quantify the signal-to-noise ratio necessary to achieve a specified measurement precision for neutron star radius. We find that accumulating 10{sup 6} counts in a pulse profile is sufficient to achieve a ≲ 5% uncertainty in the neutron star radius, which is the level of accuracy required to determine the equation of state of neutron-star matter. Finally, we formally derive the background limits that can be tolerated in the measurements of the various pulsation amplitudes as a function of the system parameters.

  6. Experimental characterization of the AFIT neutron facility. Master's thesis

    SciTech Connect (OSTI)

    Lessard, O.J.

    1993-09-01

    AFIT's Neutron Facility was characterized for room-return neutrons using a (252)Cf source and a Bonner sphere spectrometer with three experimental models, the shadow shield, the Eisenhauer, Schwartz, and Johnson (ESJ), and the polynomial models. The free-field fluences at one meter from the ESJ and polynomial models were compared to the equivalent value from the accepted experimental shadow shield model to determine the suitability of the models in the AFIT facility. The polynomial model behaved erratically, as expected, while the ESJ model compared to within 4.8% of the shadow shield model results for the four Bonner sphere calibration. The ratio of total fluence to free-field fluence at one meter for the ESJ model was then compared to the equivalent ratio obtained by a Monte Cario Neutron-Photon transport code (MCNP), an accepted computational model. The ESJ model compared to within 6.2% of the MCNP results. AFIT's fluence ratios were compared to equivalent ratios reported by three other neutron facilities which verified that AFIT's results fit previously published trends based on room volumes. The ESJ model appeared adequate for health physics applications and was chosen was chosen for calibration of the AFIT facility. Neutron Detector, Bonner Sphere, Neutron Dosimetry, Room Characterization.

  7. FAST NEUTRON SPECTROMETER

    DOE Patents [OSTI]

    Davis, F.J.; Hurst, G.S.; Reinhardt, P.W.

    1959-08-18

    An improved proton recoil spectrometer for determining the energy spectrum of a fast neutron beam is described. Instead of discriminating against and thereby"throwing away" the many recoil protons other than those traveling parallel to the neutron beam axis as do conventional spectrometers, this device utilizes protons scattered over a very wide solid angle. An ovoidal gas-filled recoil chamber is coated on the inside with a scintillator. The ovoidal shape of the sensitive portion of the wall defining the chamber conforms to the envelope of the range of the proton recoils from the radiator disposed within the chamber. A photomultiplier monitors the output of the scintillator, and a counter counts the pulses caused by protons of energy just sufficient to reach the scintillator.

  8. COMPOSITE NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Menke, J.R.

    1963-06-11

    This patent relates to a reactor having a core which comprises an inner active region and an outer active region, each region separately having a k effective less than one and a k infinity greater than one. The inner and outer regions in combination have a k effective at least equal to one and each region contributes substantially to the k effective of the reactor core. The inner region has a low moderator to fuel ratio such that the majority of fissions occurring therein are induced by neutrons having energies greater than thermal. The outer region has a high moderator to fuel ratio such that the majority of fissions occurring therein are induced by thermal neutrons. (AEC)

  9. Scintillation neutron detectors

    SciTech Connect (OSTI)

    Davidson, J.B.

    1984-01-01

    Two basic types of scintillation area neutron detectors are reviewed. The first is the prompt detector which uses photomultipliers to convert the neutron scintillations to electrical pulses. These signals are combined in weighting or encoding circuits to give event location. Several embodiments of the weighted and coded scintillator approach are mentioned. The second type of scintillation detector is based on television techniques and has a delayed readout. In this method all the light (or as much as possible) is either focused with a fast lens or is coupled by being put in direct contact with the fiber-optic faceplate of an image intensifier tube. The light from the phosphor screen is intensified and coupled to a television camera tube instead of a photomultiplier, and further amplification is produced in the camera tube by accelerating the photoelectrons in order to produce secondary electrons. (LEW)

  10. Porous material neutron detector

    DOE Patents [OSTI]

    Diawara, Yacouba; Kocsis, Menyhert

    2012-04-10

    A neutron detector employs a porous material layer including pores between nanoparticles. The composition of the nanoparticles is selected to cause emission of electrons upon detection of a neutron. The nanoparticles have a maximum dimension that is in the range from 0.1 micron to 1 millimeter, and can be sintered with pores thereamongst. A passing radiation generates electrons at one or more nanoparticles, some of which are scattered into a pore and directed toward a direction opposite to the applied electrical field. These electrons travel through the pore and collide with additional nanoparticles, which generate more electrons. The electrons are amplified in a cascade reaction that occurs along the pores behind the initial detection point. An electron amplification device may be placed behind the porous material layer to further amplify the electrons exiting the porous material layer.

  11. High intensity, pulsed thermal neutron source

    DOE Patents [OSTI]

    Carpenter, J.M.

    1973-12-11

    This invention relates to a high intensity, pulsed thermal neutron source comprising a neutron-producing source which emits pulses of fast neutrons, a moderator block adjacent to the last neutron source, a reflector block which encases the fast neutron source and the moderator block and has a thermal neutron exit port extending therethrough from the moderator block, and a neutron energy- dependent decoupling reflector liner covering the interior surfaces of the thermal neutron exit port and surrounding all surfaces of the moderator block except the surface viewed by the thermal neutron exit port. (Official Gazette)

  12. NEUTRONIC REACTOR SYSTEM

    DOE Patents [OSTI]

    Goett, J.J.

    1961-01-24

    A system is described which includes a neutronic reactor containing a dispersion of fissionable material in a liquid moderator as fuel and a conveyor to which a portion of the dispersion may be passed and wherein the self heat of the slurry evaporates the moderator. Means are provided for condensing the liquid moderator and returning it to the reactor and for conveying the dried fissionable material away from the reactor.

  13. THERMAL NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Spinrad, B.I.

    1960-01-12

    A novel thermal reactor was designed in which a first reflector formed from a high atomic weight, nonmoderating material is disposed immediately adjacent to the reactor core. A second reflector composed of a moderating material is disposed outwardly of the first reflector. The advantage of this novel reflector arrangement is that the first reflector provides a high slow neutron flux in the second reflector, where irradiation experiments may be conducted with a small effect on reactor reactivity.

  14. European Neutron Activation System.

    Energy Science and Technology Software Center (OSTI)

    2013-01-11

    Version 03 EASY-2010 (European Activation System) consists of a wide range of codes, data and documentation all aimed at satisfying the objective of calculating the response of materials irradiated in a neutron flux. The main difference from the previous version is the upper energy limit, which has increased from 20 to 60 MeV. It is designed to investigate both fusion devices and accelerator based materials test facilities that will act as intense sources of high-energymore » neutrons causing significant activation of the surrounding materials. The very general nature of the calculational method and the data libraries means that it is applicable (with some reservations) to all situations (e.g. fission reactors or neutron sources) where materials are exposed to neutrons below 60 MeV. EASY can be divided into two parts: data and code development tools and user tools and data. The former are required to develop the latter, but EASY users only need to be able to use the inventory code FISPACT and be aware of the contents of the EAF library (the data source). The complete EASY package contains the FISPACT-2007 inventory code, the EAF-2003, EAF-2005, EAF-2007 and EAF-2010 libraries, and the EASY User Interface for the Window version. The activation package EASY-2010 is the result of significant development to extend the upper energy range from 20 to 60 MeV so that it is capable of being used for IFMIF calculations. The EAF-2010 library contains 66,256 reactions, almost five times more than in EAF-2003 (12,617). Deuteron-induced and proton-induced cross section libraries are also included, and can be used with EASY to enable calculations of the activation due to deuterons and proton [2].« less

  15. NEUTRONIC REACTOR CORE

    DOE Patents [OSTI]

    Thomson, W.B.; Corbin, A. Jr.

    1961-07-18

    An improved core for a gas-cooled power reactor which admits gas coolant at high temperatures while affording strong integral supporting structure and efficient moderation of neutrons is described. The multiplicities of fuel elements constituting the critical amassment of fissionable material are supported and confined by a matrix of metallic structure which is interspersed therebetween. Thermal insulation is interposed between substantially all of the metallic matrix and the fuel elements; the insulation then defines the principal conduit system for conducting the coolant gas in heat-transfer relationship with the fuel elements. The metallic matrix itseif comprises a system of ducts through which an externally-cooled hydrogeneous liquid, such as water, is circulated to serve as the principal neutron moderant for the core and conjointly as the principal coolant for the insulated metallic structure. In this way, use of substantially neutron transparent metals, such as aluminum, becomes possible for the supporting structure, despite the high temperatures of the proximate gas. The Aircraft Nuclear Propulsion program's "R-1" reactor design is a preferred embodiment.

  16. Neutron instrumentation for biology

    SciTech Connect (OSTI)

    Mason, S.A.

    1994-12-31

    In the October 1994 round of proposals at the ILL, the external biology review sub- committee was asked to allocate neutron beam time to a wide range of experiments, on almost half the total number of scheduled neutron instruments: on 3 diffractometers, on 3 small angle scattering instruments, and on some 6 inelastic scattering spectrometers. In the 3.5 years since the temporary reactor shutdown, the ILL`s management structure has been optimized, budgets and staff have been trimmed, the ILL reactor has been re-built, and many of the instruments up-graded, many powerful (mainly Unix) workstations have been introduced, and the neighboring European Synchrotron Radiation Facility has established itself as the leading synchrotron radiation source and has started its official user program. The ILL reactor remains the world`s most intense dedicated neutron source. In this challenging context, it is of interest to review briefly the park of ILL instruments used to study the structure and energetics of small and large biological systems. A brief summary will be made of each class of experiments actually proposed in the latest ILL proposal round.

  17. Fast neutron imaging device and method

    DOE Patents [OSTI]

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

    2014-02-11

    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.

  18. Proton recoil scintillator neutron rem meter

    DOE Patents [OSTI]

    Olsher, Richard H.; Seagraves, David T.

    2003-01-01

    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.

  19. 2010 Neutron Review: ORNL Neutron Sciences Progress Report (Technical...

    Office of Scientific and Technical Information (OSTI)

    ... (6) Changing the World of Data Acquisition - Researchers at SNS are starting to ... Country of Publication: United States Language: English Subject: neutron science; ...

  20. NEUTRON MEASURING METHOD AND APPARATUS

    DOE Patents [OSTI]

    Seaborg, G.T.; Friedlander, G.; Gofman, J.W.

    1958-07-29

    A fast neutron fission detecting apparatus is described consisting of a source of fast neutrons, an ion chamber containing air, two electrodes within the ion chamber in confronting spaced relationship, a high voltage potential placed across the electrodes, a shield placed about the source, and a suitable pulse annplifier and recording system in the electrode circuit to record the impulse due to fissions in a sannple material. The sample material is coated onto the active surface of the disc electrode and shielding means of a material having high neutron capture capabilities for thermal neutrons are provided in the vicinity of the electrodes and about the ion chamber so as to absorb slow neutrons of thermal energy to effectively prevent their diffusing back to the sample and causing an error in the measurement of fast neutron fissions.

  1. Neutron scattering and absorption properties

    SciTech Connect (OSTI)

    Holden, N.E.

    1993-12-01

    The Table in this report presents an evaluated set of values for the experimental quantities, which characterize the properties for scattering and absorption of neutrons. The neutron cross section is given for room temperature neutrons, 20.43{degree}C, corresponds to a thermal neutron energy of 0.0253 electron volts (eV) or a neutron velocity of 2200 meters/second. The neutron resonance integral is defined over the energy range from 0.5 eV to 0.1 {times} 10{sup 6} eV, or 0.1 MeV. A list of the major references used is given below. The literature cutoff data is October 1993. Uncertainties are given in parentheses. Parentheses with two or more numbers indicate values to the excited states(s) and to the ground state of the product nucleus.

  2. Fundamentals of the relativistic theory of gravitation

    SciTech Connect (OSTI)

    Logunov, A.A.; Mestvirishvili, M.A.

    1986-01-01

    An extended exposition of the relativistic theory of gravitation (RTG) proposed by Logunov, Vlasov, and Mestvirishvili is presented. The RTG was constructed uniquely on the basis of the relativity principle and the geometrization principle by regarding the gravitational field as a physical field in the spirit of Faraday and Maxwell possessing energy, momentum, and spins 2 and 0. In the theory, conservation laws for the energy, momentum, and angular momentum for the matter and gravitational field taken together are strictly satisfied. The theory explains all the existing gravitational experiments. When the evolution of the universe is analyzed, the theory leads to the conclusion that the universe is infinite and flat, and it is predicted to contain a large amount of hidden mass. This missing mass exceeds by almost 40 times the amount of matter currently observed in the universe. The RTG predicts that gravitational collapse, which for a comoving observer occurs after a finite proper time, does not lead to infinite compression of matter but is halted at a certain finite density of the collapsing body. Therefore, according to the RTG there cannot be any objects in nature in which the gravitational contraction of matter to infinite density occurs, i.e., there are no black holes.

  3. APPARATUS FOR CONTROLLING NEUTRONIC REACTORS

    DOE Patents [OSTI]

    Dietrich, J.R.; Harrer, J.M.

    1958-09-16

    A device is described for rapidly cortrolling the reactivity of an active portion of a reactor. The inveniion consists of coaxially disposed members each having circumferenital sections of material having dlfferent neutron absorbing characteristics and means fur moving the members rotatably and translatably relative to each other within the active portion to vary the neutron flux therein. The angular and translational movements of any member change the neutron flux shadowing effect of that member upon the other member.

  4. Energy Literacy: Essential Principles and Fundamental Concepts for Energy

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

    Education | Department of Energy Literacy: Essential Principles and Fundamental Concepts for Energy Education Energy Literacy: Essential Principles and Fundamental Concepts for Energy Education Energy Literacy: Essential Principles and Fundamental Concepts for Energy Education News and Updates Check out our new Energy Literacy video series! The Energy Literacy Framework is also available in Spanish: Conocimiento de Energía. What is Energy Literacy? Energy Literacy is an understanding of the

  5. Uncovering Fundamental Ash-Formation Mechanisms and Potential Means to

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

    Control the Impact on DPF Performance and Engine Efficiency | Department of Energy Uncovering Fundamental Ash-Formation Mechanisms and Potential Means to Control the Impact on DPF Performance and Engine Efficiency Uncovering Fundamental Ash-Formation Mechanisms and Potential Means to Control the Impact on DPF Performance and Engine Efficiency Results illustrate ash particle growth and formation pathways, and influence of lubricant chemistry and exhaust conditions on fundamental ash

  6. Introducing Nuclear Data Evaluations of Prompt Fission Neutron Spectra

    SciTech Connect (OSTI)

    Neudecker, Denise

    2015-06-17

    Nuclear data evaluations provide recommended data sets for nuclear data applications such as reactor physics, stockpile stewardship or nuclear medicine. The evaluated data are often based on information from multiple experimental data sets and nuclear theory using statistical methods. Therefore, they are collaborative efforts of evaluators, theoreticians, experimentalists, benchmark experts, statisticians and application area scientists. In this talk, an introductions is given to the field of nuclear data evaluation at the specific example of a recent evaluation of the outgoing neutron energy spectrum emitted promptly after fission from 239Pu and induced by neutrons from thermal to 30 MeV.

  7. The Many Faces - and Phases - of Neutron Stars

    SciTech Connect (OSTI)

    Piekarewicz, J.

    2007-10-26

    Understanding the equation of state (EOS) of nuclear matter is a central goal of nuclear physics that cuts across a variety of disciplines. Indeed, the limits of nuclear existence, the collision of heavy ions, the structure of neutron stars, and the dynamics of core-collapse supernova, all depend critically on the equation of state of hadronic matter. In this contribution I will concentrate on the EOS of cold baryonic matter with special emphasis on its impact on the structure and dynamics of neutron stars. In particular, I will discuss the many fascinating phases that one encounters as one travels from the low-density crust to the high-density core.

  8. Deuterated polyethylene coatings for ultra-cold neutron applications

    SciTech Connect (OSTI)

    Brenner, Th.; Geltenbort, P.; Fierlinger, P.; Gutsmiedl, E.; Hollering, A.; Petzoldt, G.; Ruhstorfer, D.; Stuiber, St.; Taubenheim, B.; Windmayer, D.; Lauer, T.; Schroffenegger, J.; Zechlau, T.; Seemann, K. M.; Soltwedel, O.

    2015-09-21

    We report on the fabrication and use of deuterated polyethylene as a coating material for ultra-cold neutron (UCN) storage and transport. The Fermi potential has been determined to be 214 neV, and the wall loss coefficient η is 1.3 × 10{sup 4} per wall collision. The coating technique allows for a wide range of applications in this field of physics. In particular, flexible and quasi-massless UCN guides with slit-less shutters and seamless UCN storage volumes become possible. These properties enable the use in next-generation measurements of the electric dipole moment of the neutron.

  9. Nanoscale imaging of fundamental Li battery chemistry: solid...

    Office of Scientific and Technical Information (OSTI)

    Nanoscale imaging of fundamental Li battery chemistry: solid-electrolyte interphase formation and preferential growth of lithium metal nanoclusters Prev Next Title: Nanoscale ...

  10. The Department of Energy's National Security Information Fundamental...

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

    The Department of Energy's National Security Information Fundamental Classification Guidance Review The goals of this review process was to evaluate the guidance content, determine ...

  11. COLLOQUIUM: Type II Solar Radio Bursts: From Fundamental Plasma...

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

    distribution functions, the electron beams drive Langmuir waves, and the Langmuir waves couple linearly andor nonlinearly to produce the fundamental and harmonic radio emission. ...

  12. Fundamentals of XAFS (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Fundamentals of XAFS Citation Details In-Document Search Title: ... Publication Date: 2014-08-07 OSTI Identifier: 1149632 Resource Type: Journal Article ...

  13. Vehicle Technologies Office Merit Review 2015: Fundamental Studies...

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

    Office Merit Review 2014: Fundamental Studies of Lithium-Sulfur Cell Chemistry Additives and Cathode Materials for High-Energy Lithium Sulfur Batteries Vehicle Technologies...

  14. The fundamental solution of the unidirectional pulse propagation equation

    SciTech Connect (OSTI)

    Babushkin, I.; Bergé, L.

    2014-03-15

    The fundamental solution of a variant of the three-dimensional wave equation known as “unidirectional pulse propagation equation” (UPPE) and its paraxial approximation is obtained. It is shown that the fundamental solution can be presented as a projection of a fundamental solution of the wave equation to some functional subspace. We discuss the degree of equivalence of the UPPE and the wave equation in this respect. In particular, we show that the UPPE, in contrast to the common belief, describes wave propagation in both longitudinal and temporal directions, and, thereby, its fundamental solution possesses a non-causal character.

  15. Discovery of the Fundamental Mechanism of Action of Resveratrol...

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

    Discovery of the Fundamental Mechanism of Action of Resveratrol Thursday, May 28, 2015 Resveratrol is reported to extend lifespan and provide cardio-neuro-protective, ...

  16. Transition metals on the (0001) surface of graphite: Fundamental...

    Office of Scientific and Technical Information (OSTI)

    metals on the (0001) surface of graphite: Fundamental aspects of adsorption, diffusion, and morphology Citation Details In-Document Search Title: Transition metals on the...

  17. Fundamental study of the relationship of austenite-ferrite transformat...

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

    Fundamental study of the relationship of austenite-ferrite transformation details to austenite retention in carbon steels FSW & USW Solid State Joining of Magnesium to Steel ...

  18. Fundamental Research on Percussion Drilling: Improved rock mechanics...

    Office of Scientific and Technical Information (OSTI)

    Fundamental Research on Percussion Drilling: Improved rock mechanics analysis, advanced simulation technology, and full-scale laboratory investigations Citation Details In-Document...

  19. Fundamental Issues in Subzero PEMFC Startup and Operation

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

    Fundamental issues in subzero PEMFC startup and operation Jeremy P. Meyers February 1, 2005 DOE Freeze Workshop Outline of presentation * Motivation * Stack performance * ...

  20. NEUTRON ABSORPTION AND SHIELDING DEVICE

    DOE Patents [OSTI]

    Axelrad, I.R.

    1960-06-21

    A neutron absorption and shielding device is described which is adapted for mounting in a radiation shielding wall surrounding a radioactive area through which instrumentation leads and the like may safely pass without permitting gamma or neutron radiation to pass to the exterior. The shielding device comprises a container having at least one nonrectilinear tube or passageway means extending therethrough, which is adapted to contain instrumentation leads or the like, a layer of a substance capable of absorbing gamma rays, and a solid resinous composition adapted to attenuate fast-moving neutrons and capture slow- moving or thermal neutrons.

  1. 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)

    1985-01-01

    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.

  2. Portable neutron spectrometer and dosimeter

    DOE Patents [OSTI]

    Waechter, D.A.; Erkkila, B.H.; Vasilik, D.G.

    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.

  3. Advanced Neutron Source (ANS) Project

    SciTech Connect (OSTI)

    Campbell, J.H.; Selby, D.L.; Harrington, R.M.; Peretz, F.J.

    1991-02-01

    This report discusses the research and development, design and safety of the Advanced Neutron Source at Oak Ridge National Laboratory. (LSP)

  4. NEUTRON IMAGING, RADIOGRAPHY AND TOMOGRAPHY.

    SciTech Connect (OSTI)

    SMITH,G.C.

    2002-03-01

    Neutrons are an invaluable probe in a wide range of scientific, medical and commercial endeavors. Many of these applications require the recording of an image of the neutron signal, either in one-dimension or in two-dimensions. We summarize the reactions of neutrons with the most important elements that are used for their detection. A description is then given of the major techniques used in neutron imaging, with emphasis on the detection media and position readout principle. Important characteristics such as position resolution, linearity, counting rate capability and sensitivity to gamma-background are discussed. Finally, the application of a subset of these instruments in radiology and tomography is described.

  5. Big Bang Day : Physics Rocks

    ScienceCinema (OSTI)

    None

    2011-04-25

    Is particle physics the new rock 'n' roll? The fundamental questions about the nature of the universe that particle physics hopes to answer have attracted the attention of some very high profile and unusual fans. Alan Alda, Ben Miller, Eddie Izzard, Dara O'Briain and John Barrowman all have interests in this branch of physics. Brian Cox - CERN physicist, and former member of 90's band D:Ream, tracks down some very well known celebrity enthusiasts and takes a light-hearted look at why this subject can appeal to all of us.

  6. Big Bang Day : Physics Rocks

    SciTech Connect (OSTI)

    2009-10-07

    Is particle physics the new rock 'n' roll? The fundamental questions about the nature of the universe that particle physics hopes to answer have attracted the attention of some very high profile and unusual fans. Alan Alda, Ben Miller, Eddie Izzard, Dara O'Briain and John Barrowman all have interests in this branch of physics. Brian Cox - CERN physicist, and former member of 90's band D:Ream, tracks down some very well known celebrity enthusiasts and takes a light-hearted look at why this subject can appeal to all of us.

  7. Inquiring Minds - Questions About Physics

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

    Consequences of Superstring Theory Animesh writes: I am doing my B.Tech in electronics engineering ,with a minor in particle physics at IIT,KANPUR,INDIA. I would like to know the following: WHAT WILL BE THE CONSEQUENCE OF THE SUCCESS OF THE SUPER STRING THEORY? i.e,WHEN THE FUNDAMENTAL PHOMENON OF ALL THE FORCES WILL BE KNOWN,WILL PHYSICS BE EXHAUSTED? Thanking you, ANIMESH D., IIT,KANPUR. Hi ANIMESH, If the superstring theory is true, we have then a very fundemental theory of physics. We could

  8. Teaching symmetry in the introductory physics curriculum

    SciTech Connect (OSTI)

    Hill, C. T.; Lederman, L. M.

    2000-01-01

    Modern physics is largely defined by fundamental symmetry principles and Noether's Theorem. Yet these are not taught, or rarely mentioned, to beginning students, thus missing an opportunity to reveal that the subject of physics is as lively and contemporary as molecular biology, and as beautiful as the arts. We prescribe a symmetry module to insert into the curriculum, of a week's length.

  9. Theoretical Nuclear Physics - Research - Cyclotron Institute

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

    Theoretical Nuclear Physics By addressing this elastic scattering indirect technique, we hope that more accurate measurements of elastic scattering data will provide very important astrophysical information. Progress toward understanding the structure and behavior of strongly interacting many-body systems requires detailed theoretical study. The theoretical physics program concentrates on the development of fundamental and phenomenological models of nuclear behavior. In some systems, the

  10. Fundamentals of Materials, Techniques, and Instrumentation for OSL and FNTD Dosimetry

    SciTech Connect (OSTI)

    Akselrod, M. S.

    2011-05-05

    The optically stimulated luminescence (OSL) technique has already become a successful commercial tool in personal radiation dosimetry, medical dosimetry, diagnostic imaging, geological and archeological dating. This review briefly describes the history and fundamental principles of OSL materials, methods and instrumentation. The advantages of OSL technology and instrumentation in comparison with thermoluminescent technique are analyzed. Progress in material and detector engineering has allowed new and promising developments regarding OSL applications in the medical field. Special attention is dedicated to Al{sub 2}O{sub 3}:C as a material of choice for many dosimetric applications. Different aspects of OSL theory, materials optical and dosimetric properties, instrumentation, and data processing algorithms are described. The next technological breakthrough was done with Fluorescent Nuclear Track Detectors (FNTD) that have some important advantages in measuring fast neutron and high energy heavy charge particles that have become the latest tool in radiation therapy. New Mg-doped aluminum oxide crystals and novel type of imaging instrumentation for FNTD technology are discussed with regard to application in mixed neutron-gamma fields, medical dosimetry and radiobiological research.

  11. Operational health physics training

    SciTech Connect (OSTI)

    1992-06-01

    The initial four sections treat basic information concerning atomic structure and other useful physical quantities, natural radioactivity, the properties of {alpha}, {beta}, {gamma}, x rays and neutrons, and the concepts and units of radiation dosimetry (including SI units). Section 5 deals with biological effects and the risks associated with radiation exposure. Background radiation and man-made sources are discussed next. The basic recommendations of the ICRP concerning dose limitations: justification, optimization (ALARA concepts and applications) and dose limits are covered in Section seven. Section eight is an expanded version of shielding, and the internal dosimetry discussion has been extensively revised to reflect the concepts contained in the MIRD methodology and ICRP 30. The remaining sections discuss the operational health physics approach to monitoring radiation. Individual sections include radiation detection principles, instrument operation and counting statistics, health physics instruments and personnel monitoring devices. The last five sections deal with the nature of, operation principles of, health physics aspects of, and monitoring approaches to air sampling, reactors, nuclear safety, gloveboxes and hot cells, accelerators and x ray sources. Decontamination, waste disposal and transportation of radionuclides are added topics. Several appendices containing constants, symbols, selected mathematical topics, and the Chart of the Nuclides, and an index have been included.

  12. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

    SciTech Connect (OSTI)

    Makowska, Małgorzata G.; Theil Kuhn, Luise; Cleemann, Lars N.; Lauridsen, Erik M.; Bilheux, Hassina Z.; Molaison, Jamie J.; Santodonato, Louis J.; Tremsin, Anton S.; Grosse, Mirco; Morgano, Manuel; Kabra, Saurabh; Strobl, Markus

    2015-12-17

    In high material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible with any other technique. Our paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 degrees C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging with diffraction measurements. Design, special features, and specification of the furnace are described. In addition, examples of experiments successfully performed at various neutron facilities with the furnace, as well as examples of possible applications are presented. Our work covers a broad field of research from fundamental to technological investigations of various types of materials and components.

  13. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

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

    Makowska, Małgorzata G.; Theil Kuhn, Luise; Cleemann, Lars N.; Lauridsen, Erik M.; Bilheux, Hassina Z.; Molaison, Jamie J.; Santodonato, Louis J.; Tremsin, Anton S.; Grosse, Mirco; Morgano, Manuel; et al

    2015-12-17

    In high material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible with any other technique. Our paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 degrees C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging with diffraction measurements. Design, special features, and specification of the furnace are described. In addition,more » examples of experiments successfully performed at various neutron facilities with the furnace, as well as examples of possible applications are presented. Our work covers a broad field of research from fundamental to technological investigations of various types of materials and components.« less

  14. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

    SciTech Connect (OSTI)

    Makowska, Małgorzata G.; Theil Kuhn, Luise; Cleemann, Lars N.; Lauridsen, Erik M.; Bilheux, Hassina Z.; Molaison, Jamie J.; Santodonato, Louis J.; Tremsin, Anton S.; Grosse, Mirco; Morgano, Manuel; Kabra, Saurabh; Strobl, Markus

    2015-12-15

    High material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible with any other technique. This paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 °C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging with diffraction measurements. Design, special features, and specification of the furnace are described. In addition, examples of experiments successfully performed at various neutron facilities with the furnace, as well as examples of possible applications are presented. This covers a broad field of research from fundamental to technological investigations of various types of materials and components.

  15. Electroweak bremsstrahlung from neutron-neutron scattering

    SciTech Connect (OSTI)

    Li Yi; Liou, M. K.; Schreiber, W. M.

    2009-09-15

    Background: Nucleon-nucleon (NN) bremsstrahlung processes NN{gamma} (nn{gamma}, np{gamma}, and pp{gamma}) have been extensively investigated. Neutrino-pair bremsstrahlung processes from nucleon-nucleon scattering NN{nu}{nu} (nn{nu}{nu}, np{nu}{nu}, and pp{nu}{nu}) have recently attracted attention in studies of neutrino emission in neutron stars. The calculated NN{nu}{nu} cross sections (or emissivities) are found to be sensitive to the two-nucleon dynamical model used in the calculations. Purpose and Method: A realistic one-boson-exchange (ROBE) model for NN interactions is used to construct the electroweak bremsstrahlung amplitudes using the well-known nucleon electromagnetic and weak interaction vertices. The constructed nn{gamma} and nn{nu}{nu} amplitudes are investigated by applying them to calculate nn{gamma} and nn{nu}{nu} cross sections, respectively. Results: (i) The 190-MeV ROBE nn{gamma} cross sections agree well with those calculated using the TuTts amplitude, but they are in disagreement with those calculated using the Low amplitude. (ii) The calculated nn{nu}{nu} cross sections using the ROBE amplitude at the neutrino-pair energy {omega} = 1 MeV are in quantitative agreement with those calculated by Timmermans et al.[Phys. Rev. C 65, 064007 (2002)], who used the leading-order term of the soft neutrino-pair bremsstrahlung amplitude. Conclusions: The nn{gamma} amplitude in the ROBE approach, which obeys the soft-photon theorem, has a predictive power similar to that of the TuTts amplitude. The nn{nu}{nu} amplitude in the ROBE approach, which is consistent with the soft neutrino-pair bremsstrahlung theorem, has a predictive power similar to that of the soft neutrino-pair bremsstrahlung amplitude of Timmermans et al. in the low neutrino-pair energy region.

  16. Neutron multiplicity ,easurements With 3He alternative: Straw neutron detectors

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

    Mukhopadhyay, Sanjoy; Wolff, Ronald S.; Meade, John A.; Detweiler, Ryan; Maurer, Richard J.; Mitchell, Stephen E.; Guss, Paul P.; Lacy, Jeffrey L.; Sun, Liang; Athanasiades, Athanasios

    2015-01-27

    Counting neutrons emitted by special nuclear material (SNM) and differentiating them from the background neutrons of various origins is the most effective passive means of detecting SNM. Unfortunately, neutron detection, counting, and partitioning in a maritime environment are complex due to the presence of high-multiplicity spallation neutrons (commonly known as “ship effect”) and to the complicated nature of the neutron scattering in that environment. In this study, a prototype neutron detector was built using 10B as the converter in a special form factor called “straws” that would address the above problems by looking into the details of multiplicity distributions ofmore » neutrons originating from a fissioning source. This paper describes the straw neutron multiplicity counter (NMC) and assesses the performance with those of a commercially available fission meter. The prototype straw neutron detector provides a large-area, efficient, lightweight, more granular (than fission meter) neutron-responsive detection surface (to facilitate imaging) to enhance the ease of application of fission meters. Presented here are the results of preliminary investigations, modeling, and engineering considerations leading to the construction of this prototype. This design is capable of multiplicity and Feynman variance measurements. This prototype may lead to a near-term solution to the crisis that has arisen from the global scarcity of 3He by offering a viable alternative to fission meters. This paper describes the work performed during a 2-year site-directed research and development (SDRD) project that incorporated straw detectors for neutron multiplicity counting. The NMC is a two-panel detector system. We used 10B (in the form of enriched boron carbide: 10B4C) for neutron detection instead of 3He. In the first year, the project worked with a panel of straw neutron detectors, investigated its characteristics, and developed a data acquisition (DAQ) system to collect

  17. Fundamental Mechanisms Driving the Amorphous to Crystalline Phase Transformation

    SciTech Connect (OSTI)

    Reed, B W; Browning, N D; Santala, M K; LaGrange, T; Gilmer, G H; Masiel, D J; Campbell, G H; Raoux, S; Topuria, T; Meister, S; Cui, Y

    2011-01-04

    Phase transformations are ubiquitous, fundamental phenomena that lie at the heart of many structural, optical and electronic properties in condensed matter physics and materials science. Many transformations, especially those occurring under extreme conditions such as rapid changes in the thermodynamic state, are controlled by poorly understood processes involving the nucleation and quenching of metastable phases. Typically these processes occur on time and length scales invisible to most experimental techniques ({micro}s and faster, nm and smaller), so our understanding of the dynamics tends to be very limited and indirect, often relying on simulations combined with experimental study of the ''time infinity'' end state. Experimental techniques that can directly probe phase transformations on their proper time and length scales are therefore key to providing fundamental insights into the whole area of transformation physics and materials science. LLNL possesses a unique dynamic transmission electron microscope (DTEM) capable of taking images and diffraction patterns of laser-driven material processes with resolution measured in nanometers and nanoseconds. The DTEM has previously used time-resolved diffraction patterns to quantitatively study phase transformations that are orders of magnitude too fast for conventional in situ TEM. More recently the microscope has demonstrated the ability to directly image a reaction front moving at {approx}13 nm/ns and the nucleation of a new phase behind that front. Certain compound semiconductor phase change materials, such as Ge{sub 2}Sb{sub 2}Te{sub 5} (GST), Sb{sub 2}Te and GeSb, exhibit a technologically important series of transformations on scales that fall neatly into the performance specifications of the DTEM. If a small portion of such material is heated above its melting point and then rapidly cooled, it quenches into an amorphous state. Heating again with a less intense pulse leads to recrystallization into a vacancy

  18. SciTech Connect: "neutron scattering"

    Office of Scientific and Technical Information (OSTI)

    neutron scattering" Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: "neutron scattering" Semantic Semantic Term Title: Full Text: Bibliographic...

  19. High energy neutron Computed Tomography developed

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

    objects. May 9, 2014 Neutron tomography horizontal "slice" of a tungsten and polyethylene test object containing tungsten carbide BBs. Neutron tomography horizontal "slice"...

  20. Efficiency measurements using tagged neutrons (Conference) |...

    Office of Scientific and Technical Information (OSTI)

    Efficiency measurements using tagged neutrons Citation Details In-Document Search Title: Efficiency measurements using tagged neutrons Authors: Taddeucci, Terry N 1 + Show Author ...

  1. Efficiency measurements using tagged neutrons (Conference) |...

    Office of Scientific and Technical Information (OSTI)

    Efficiency measurements using tagged neutrons Citation Details In-Document Search Title: Efficiency measurements using tagged neutrons You are accessing a document from the ...

  2. NEUTRONIC REACTOR CONSTRUCTION

    DOE Patents [OSTI]

    Vernon, H.C.; Goett, J.J.

    1958-09-01

    A cover device is described for the fuel element receiving tube of a neutronic reactor of the heterogeneous, water cooled type wherein said tubes are arranged in a moderator with their longitudinal axes vertical. The cover is provided with means to support a rod-type fuel element from the bottom thereof and means to lock the cover in place, the latter being adapted for remote operation. This cover device is easily removable and seals the opening in the upper end of the fuel tube against leakage of coolant.

  3. Accurate Development of Thermal Neutron Scattering Cross Section Libraries

    SciTech Connect (OSTI)

    Hawari, Ayman; Dunn, Michael

    2014-06-10

    The objective of this project is to develop a holistic (fundamental and accurate) approach for generating thermal neutron scattering cross section libraries for a collection of important enutron moderators and reflectors. The primary components of this approach are the physcial accuracy and completeness of the generated data libraries. Consequently, for the first time, thermal neutron scattering cross section data libraries will be generated that are based on accurate theoretical models, that are carefully benchmarked against experimental and computational data, and that contain complete covariance information that can be used in propagating the data uncertainties through the various components of the nuclear design and execution process. To achieve this objective, computational and experimental investigations will be performed on a carefully selected subset of materials that play a key role in all stages of the nuclear fuel cycle.

  4. A High Temperature-Tolerant and Radiation-Resistant In-Core Neutron Sensor for Advanced Reactors. Final report

    SciTech Connect (OSTI)

    Cao, Lei; Miller, Don

    2015-01-23

    The objectives of this project are to develop a small and reliable gallium nitride (GaN) neutron sensor that is capable of withstanding high neutron fluence and high temperature, isolating gamma background, and operating in a wide dynamic range. The first objective will be the understanding of the fundamental materials properties and electronic response of a GaN semiconductor materials and device in an environment of high temperature and intense neutron field. To achieve such goal, an in-situ study of electronic properties of GaN device such as I-V, leakage current, and charge collection efficiency (CCE) in high temperature using an external neutron beam will be designed and implemented. We will also perform in-core irradiation of GaN up to the highest yet fast neutron fluence and an off-line performance evaluation.

  5. Neutrons for technology and science

    SciTech Connect (OSTI)

    Aeppli, G.

    1995-10-01

    We reviewed recent work using neutrons generated at nuclear reactors an accelerator-based spallation sources. Provided that large new sources become available, neutron beams will continue to have as great an impact on technology and science as in the past.

  6. Fission fragment driven neutron source

    DOE Patents [OSTI]

    Miller, Lowell G.; Young, Robert C.; Brugger, Robert M.

    1976-01-01

    Fissionable uranium formed into a foil is bombarded with thermal neutrons in the presence of deuterium-tritium gas. The resulting fission fragments impart energy to accelerate deuterium and tritium particles which in turn provide approximately 14 MeV neutrons by the reactions t(d,n).sup.4 He and d(t,n).sup.4 He.

  7. Maintenance neutron coincidence counter manual

    SciTech Connect (OSTI)

    Krick, M.S.; Polk, P.J.; Atencio, J.D.

    1989-09-01

    A compact thermal-neutron coincidence counter has been constructed specifically for use by the International Atomic Energy Agency as a reference neutron detector for maintenance activities. The counter is designed for use only with {sup 252}Cf sources in SR-CF-100 capsules. This manual describes the detector's mechanical and electrical components and its operating characteristics. 2 refs., 8 figs.

  8. High power neutron production targets

    SciTech Connect (OSTI)

    Wender, S.

    1996-06-01

    The author describes issues of concern in the design of targets and associated systems for high power neutron production facilities. The facilities include uses for neutron scattering, accelerator driven transmutation, accelerator production of tritium, short pulse spallation sources, and long pulse spallation sources. Each of these applications requires a source with different design needs and consequently different implementation in practise.

  9. Measuring neutron spectra in radiotherapy using the nested neutron spectrometer

    SciTech Connect (OSTI)

    Maglieri, Robert Evans, Michael; Seuntjens, Jan; Kildea, John; Licea, Angel

    2015-11-15

    Purpose: Out-of-field neutron doses resulting from photonuclear interactions in the head of a linear accelerator pose an iatrogenic risk to patients and an occupational risk to personnel during radiotherapy. To quantify neutron production, in-room measurements have traditionally been carried out using Bonner sphere systems (BSS) with activation foils and TLDs. In this work, a recently developed active detector, the nested neutron spectrometer (NNS), was tested in radiotherapy bunkers. Methods: The NNS is designed for easy handling and is more practical than the traditional BSS. Operated in current-mode, the problem of pulse pileup due to high dose-rates is overcome by measuring current, similar to an ionization chamber. In a bunker housing a Varian Clinac 21EX, the performance of the NNS was evaluated in terms of reproducibility, linearity, and dose-rate effects. Using a custom maximum-likelihood expectation–maximization algorithm, measured neutron spectra at various locations inside the bunker were then compared to Monte Carlo simulations of an identical setup. In terms of dose, neutron ambient dose equivalents were calculated from the measured spectra and compared to bubble detector neutron dose equivalent measurements. Results: The NNS-measured spectra for neutrons at various locations in a treatment room were found to be consistent with expectations for both relative shape and absolute magnitude. Neutron fluence-rate decreased with distance from the source and the shape of the spectrum changed from a dominant fast neutron peak near the Linac head to a dominant thermal neutron peak in the moderating conditions of the maze. Monte Carlo data and NNS-measured spectra agreed within 30% at all locations except in the maze where the deviation was a maximum of 40%. Neutron ambient dose equivalents calculated from the authors’ measured spectra were consistent (one standard deviation) with bubble detector measurements in the treatment room. Conclusions: The NNS may

  10. ATRC Neutron Detector Testing Quick Look Report

    SciTech Connect (OSTI)

    Troy C. Unruh; Benjamin M. Chase; Joy L. Rempe

    2013-08-01

    As part of the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) program, a joint Idaho State University (ISU) / French Alternative Energies and Atomic Energy Commission (CEA) / Idaho National Laboratory (INL) project was initiated in FY-10 to investigate the feasibility of using neutron sensors to provide online measurements of the neutron flux and fission reaction rate in the ATR Critical Facility (ATRC). A second objective was to provide initial neutron spectrum and flux distribution information for physics modeling and code validation using neutron activation based techniques in ATRC as well as ATR during depressurized operations. Detailed activation spectrometry measurements were made in the flux traps and in selected fuel elements, along with standard fission rate distribution measurements at selected core locations. These measurements provide additional calibration data for the real-time sensors of interest as well as provide benchmark neutronics data that will be useful for the ATR Life Extension Program (LEP) Computational Methods and V&V Upgrade project. As part of this effort, techniques developed by Prof. George Imel will be applied by Idaho State University (ISU) for assessing the performance of various flux detectors to develop detailed procedures for initial and follow-on calibrations of these sensors. In addition to comparing data obtained from each type of detector, calculations will be performed to assess the performance of and reduce uncertainties in flux detection sensors and compare data obtained from these sensors with existing integral methods employed at the ATRC. The neutron detectors required for this project were provided to team participants at no cost. Activation detectors (foils and wires) from an existing, well-characterized INL inventory were employed. Furthermore, as part of an on-going ATR NSUF international cooperation, the CEA sent INL three miniature fission chambers (one for detecting fast flux and two for

  11. Fast neutron environments.

    SciTech Connect (OSTI)

    Buchheit, Thomas Edward; Kotula, Paul Gabriel; Lu, Ping; Brewer, Luke N.; Goods, Steven Howard; Foiles, Stephen Martin; Puskar, Joseph David; Hattar, Khalid Mikhiel; Doyle, Barney Lee; Boyce, Brad Lee; Clark, Blythe G.

    2011-10-01

    The goal of this LDRD project is to develop a rapid first-order experimental procedure for the testing of advanced cladding materials that may be considered for generation IV nuclear reactors. In order to investigate this, a technique was developed to expose the coupons of potential materials to high displacement damage at elevated temperatures to simulate the neutron environment expected in Generation IV reactors. This was completed through a high temperature high-energy heavy-ion implantation. The mechanical properties of the ion irradiated region were tested by either micropillar compression or nanoindentation to determine the local properties, as a function of the implantation dose and exposure temperature. In order to directly compare the microstructural evolution and property degradation from the accelerated testing and classical neutron testing, 316L, 409, and 420 stainless steels were tested. In addition, two sets of diffusion couples from 316L and HT9 stainless steels with various refractory metals. This study has shown that if the ion irradiation size scale is taken into consideration when developing and analyzing the mechanical property data, significant insight into the structural properties of the potential cladding materials can be gained in about a week.

  12. Concept of DT fuel cycle for a fusion neutron source

    SciTech Connect (OSTI)

    Anan'ev, S.; Spitsyn, A.V.; Kuteev, B.V.; Cherkez, D.I.; Shirnin, P.N.; Kazakovsky, N.T.

    2015-03-15

    A concept of DT-fusion neutron source (FNS) with the neutron yield higher than 10{sup 18} neutrons per second is under design in Russia. Such a FNS is of interest for many applications: 1) basic and applied research (neutron scattering, etc); 2) testing the structural materials for fusion reactors; 3) control of sub-critical nuclear systems and 4) nuclear waste processing (including transmutation of minor actinides). This paper describes the fuel cycle concept of a compact fusion neutron source based on a small spherical tokamak (FNS-ST) with a MW range of DT fusion power and considers the key physics issues of this device. The major and minor radii are ∼0.5 and ∼0.3 m, magnetic field ∼1.5 T, heating power less than 15 MW and plasma current 1-2 MA. The system provides the fuel mixture with equal fractions of D and T (D:T = 1:1) for all FNS technology systems. (authors)

  13. New Physics at CDF

    SciTech Connect (OSTI)

    Rossi, Melisa; /INFN, Trieste

    2010-06-01

    The Standard Model (SM) of particle interactions is one of the major achievements of fundamental science. However, despite its success in predicting experimental results through the years, several fundamental issues are left open such as: the origin of dark matter in the universe, the existence of a unifying theory of all known forces and interactions, why particles have the masses we observe and the hierarchy problem. Supersymmetry (SUSY) is one of the possible extensions of the SM. It proposes an additional symmetry that predicts the existence of an additional boson (fermion) for each SM fermion (boson). The appeal of SUSY is closely related to the fact that it naturally solves several of the open questions of the SM. Thus it is extensively tested in an experiment as CDF where many of its signatures can be searched for. On the other hand there is still no compelling reason to exclude other scenarios like Extra-dimensions and New Gauge Interaction Models, a priori. The CDF program in physics beyond the SM is quite rich and here we present some representative searches subdivided in two main categories: SUSY and non-SUSY searches. We present the current status of searches for physics beyond the Standard Model at the Tevatron 1.96-TeV proton-antiproton collider using data collected with the CDF experiment. We cover searches for supersymmetry, extra dimensions and new gauge bosons.

  14. Physics Integration KErnels (PIKE)

    Energy Science and Technology Software Center (OSTI)

    2014-07-31

    Pike is a software library for coupling and solving multiphysics applications. It provides basic interfaces and utilities for performing code-to-code coupling. It provides simple “black-box” Picard iteration methods for solving the coupled system of equations including Jacobi and Gauss-Seidel solvers. Pike was developed originally to couple neutronics and thermal fluids codes to simulate a light water nuclear reactor for the Consortium for Simulation of Light-water Reactors (CASL) DOE Energy Innovation Hub. The Pike library containsmore » no physics and just provides interfaces and utilities for coupling codes. It will be released open source under a BSD license as part of the Trilinos solver framework (trilinos.org) which is also BSD. This code provides capabilities similar to other open source multiphysics coupling libraries such as LIME, AMP, and MOOSE.« less

  15. Graphical User Interface for Simplified Neutron Transport Calculations

    SciTech Connect (OSTI)

    Schwarz, Randolph; Carter, Leland L

    2011-07-18

    A number of codes perform simple photon physics calculations. The nuclear industry is lacking in similar tools to perform simplified neutron physics shielding calculations. With the increased importance of performing neutron calculations for homeland security applications and defense nuclear nonproliferation tasks, having an efficient method for performing simple neutron transport calculations becomes increasingly important. Codes such as Monte Carlo N-particle (MCNP) can perform the transport calculations; however, the technical details in setting up, running, and interpreting the required simulations are quite complex and typically go beyond the abilities of most users who need a simple answer to a neutron transport calculation. The work documented in this report resulted in the development of the NucWiz program, which can create an MCNP input file for a set of simple geometries, source, and detector configurations. The user selects source, shield, and tally configurations from a set of pre-defined lists, and the software creates a complete MCNP input file that can be optionally run and the results viewed inside NucWiz.

  16. Feasibility Study for a Plasma Dynamo Facility to Investigate Fundamental Processes in Plasma Astrophysics. Final report

    SciTech Connect (OSTI)

    Forest, Cary B.

    2013-09-19

    The scientific equipment purchased on this grant was used on the Plasma Dynamo Prototype Experiment as part of Professor Forest's feasibility study for determining if it would be worthwhile to propose building a larger plasma physics experiment to investigate various fundamental processes in plasma astrophysics. The initial research on the Plasma Dynamo Prototype Experiment was successful so Professor Forest and Professor Ellen Zweibel at UW-Madison submitted an NSF Major Research Instrumentation proposal titled "ARRA MRI: Development of a Plasma Dynamo Facility for Experimental Investigations of Fundamental Processes in Plasma Astrophysics." They received funding for this project and the Plasma Dynamo Facility also known as the "Madison Plasma Dynamo Experiment" was constructed. This experiment achieved its first plasma in the fall of 2012 and U.S. Dept. of Energy Grant No. DE-SC0008709 "Experimental Studies of Plasma Dynamos," now supports the research.

  17. Solution-grown crystals for neutron radiation detectors, and methods of solution growth

    DOE Patents [OSTI]

    Zaitseva, Natalia P.; Hull, Giulia; Cherepy, Nerine J.; Payne, Stephen A.; Stoeffl, Wolfgang

    2012-06-26

    A method according to one embodiment includes growing an organic crystal from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source. A system according to one embodiment includes an organic crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source; and a photodetector for detecting the signal response of the organic crystal. A method according to another embodiment includes growing an organic crystal from solution, the organic crystal being large enough to exhibit a detectable signal response signature for neutrons from a radioactive source. An organic crystal according to another embodiment includes an organic crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source, wherein the organic crystal has a length of greater than about 1 mm in one dimension.

  18. Advancing the Fundamental Understanding of Fission: 2014 LDRD...

    Office of Scientific and Technical Information (OSTI)

    Subject: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 07 ISOTOPE AND RADIATION SOURCES; 73 NUCLEAR PHYSICS AND ...

  19. Neutron capture therapy with deep tissue penetration using capillary neutron focusing

    DOE Patents [OSTI]

    Peurrung, Anthony J.

    1997-01-01

    An improved method for delivering thermal neutrons to a subsurface cancer or tumor which has been first doped with a dopant having a high cross section for neutron capture. The improvement is the use of a guide tube in cooperation with a capillary neutron focusing apparatus, or neutron focusing lens, for directing neutrons to the tumor, and thereby avoiding damage to surrounding tissue.

  20. Boron nitride solid state neutron detector

    DOE Patents [OSTI]

    Doty, F. Patrick

    2004-04-27

    The present invention describes an apparatus useful for detecting neutrons, and particularly for detecting thermal neutrons, while remaining insensitive to gamma radiation. Neutrons are detected by direct measurement of current pulses produced by an interaction of the neutrons with hexagonal pyrolytic boron nitride.

  1. Nuclear Physics

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

    Nuclear Physics Nuclear Physics Enabling remarkable discoveries and tools that transform our understanding of energy and matter and advance national, economic, and energy security. Isotopes» A roadmap of matter that will help unlock the secrets of how the universe is put together The DOE Office of Science's Nuclear Physics (NP) program supports the experimental and theoretical research needed to create this roadmap. This quest requires a broad approach to different, but related, scientific

  2. Planetary Physics

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

    planetary physics Planetary Physics Some of the most intriguing NIF experiments test the physics believed to determine the structures of planets down to their cores, both in our solar system and beyond. In particular, scientists are using NIF to "explore" recently discovered exoplanets by duplicating the extreme conditions thought to exist in their interiors. Hundreds of extrasolar planets have been identified, some smaller than Earth and others a dozen times more massive than Jupiter.

  3. Plasma Physics

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

    plasma physics Plasma Physics Almost all of the observable matter in the universe is in the plasma state. Formed at high temperatures, plasmas consist of freely moving ions and free electrons. They are often called the "fourth state of matter" because their unique physical properties distinguish them from solids, liquids and gases. Plasma densities and temperatures vary widely, from the cold gases of interstellar space to the extraordinarily hot, dense cores of stars and inside a

  4. OSTIblog Articles in the Spallation Neutron Source Topic | OSTI, US Dept of

    Office of Scientific and Technical Information (OSTI)

    Energy Office of Scientific and Technical Information Spallation Neutron Source Topic The NXS Class of 2014 by Kathy Chambers 19 Nov, 2014 in Every summer for the past 16 years, the Department of Energy has invited the best and brightest graduates from across the country to attend the National School on Neutron and X-ray Scattering (NXS). This year, 65 graduate students attending North American universities, and studying physics, chemistry, materials science, or related fields, participated

  5. Method to Reduce Neutron Production in Small Clean Fusion Reactors Inventor

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

    --- Samuel A. Cohen | Princeton Plasma Physics Lab Method to Reduce Neutron Production in Small Clean Fusion Reactors Inventor --- Samuel A. Cohen This invention describes a method to reduce neutron production of D-3He-fueled, steady state, small FRC fusion reactors using periodic, co-streaming, energetic ion beams generated by RF. Use of this method will lessen damage to and activation of reactor components and, in doing so, can advance the development of fusion reactors for electrical

  6. Evidence of a halo formation mechanism in the Spallation Neutron Source

    Office of Scientific and Technical Information (OSTI)

    linac (Journal Article) | SciTech Connect Journal Article: Evidence of a halo formation mechanism in the Spallation Neutron Source linac Citation Details In-Document Search Title: Evidence of a halo formation mechanism in the Spallation Neutron Source linac Authors: Jeon, Dong-O Publication Date: 2013-04-23 OSTI Identifier: 1091911 Type: Published Article Journal Name: Physical Review Special Topics - Accelerators and Beams Additional Journal Information: Journal Volume: 16; Journal Issue:

  7. Physics Topics - Plasma Couette Experiment - Cary Forest Group - UW Plasma

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

    Physics Physics Topics UW Madison Plasma Couette Experiment Physics Topics PCX HomeResearch MissionPhysics TopicsDeviceDiagnosticsContacts LinksPCX People CPLA Home Directory Publications Links University of Wisconsin Physics Department Department of Energy National Science Foundation Accretion Accretion is a fundamental process in astrophysics by which virtually all astrophysical bodies are formed. Due to gravity, the interstellar gas and plasma collapses into rotating disks around the

  8. Neutron Imaging Developments at LANSCE

    SciTech Connect (OSTI)

    Nelson, Ronald Owen; Hunter, James F.; Schirato, Richard C.; Vogel, Sven C.; Swift, Alicia L.; Ickes, Timothy Lee; Ward, William Carl; Losko, Adrian Simon; Tremsin, Anton; Sevanto, Sanna Annika; Espy, Michelle A.; Dickman, Lee Thoresen; Malone, Michael

    2015-10-29

    Thermal, epithermal, and high-energy neutrons are available from two spallation sources at the 800 MeV proton accelerator. Improvements in detectors and computing have enabled new capabilities that use the pulsed beam properties at LANSCE; these include amorphous Si (aSi) detectors, intensified charge-coupled device cameras, and micro-channel plates. Applications include water flow in living specimens, inclusions and fission products in uranium oxide, and high-energy neutron imaging using an aSi flat panel with ZnS(Ag) scintillator screen. images of a metal/plastic cylinder from photons, low-energy and high-energy neutrons are compared.

  9. Physical Sciences

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

    and the universe around us. Physics Division researchers are studying these interactions from the outermost reaches of the cosmos, to the innermost confines of subatomic particles....

  10. physical security

    National Nuclear Security Administration (NNSA)

    5%2A en Physical Security Systems http:nnsa.energy.govaboutusourprogramsnuclearsecurityphysicalsecuritysystems

  11. Uncovering Fundamental Ash-Formation Mechanisms and Potential...

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

    Results illustrate ash particle growth and formation pathways, and influence of lubricant chemistry and exhaust conditions on fundamental ash properties deer12kamp.pdf (9.21 MB) ...

  12. Expanding the Fundamental Chemistry of Thorium Through the Synthesis...

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

    Expanding the Fundamental Chemistry of Thorium Through the Synthesis and Reactivity of the First Molecular Complexes of Th(II) and New Classes of Th(III) and Th(IV) August 29, 2016 ...

  13. Proton Dripping Tests a Fundamental Force of Nature

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

    off, similar to the water in this photo, leaving an oxygen-13 nucleus behind. Like gravity, the strong interaction is a fundamental force of nature. It is the essential "glue"...

  14. Updated flux information for neutron scattering and irradiation facilities at the BNL High Flux Beam Reactor

    SciTech Connect (OSTI)

    Holden, N.E.; Hu, J.P.; Reciniello, R.N.; Sengupta, S.; Greenwood, L.R.; Farrell, K.

    1997-08-01

    The HFBR is a heavy water, D{sub 2}O, cooled and moderated reactor with twenty-eight fuel elements containing a maximum of 9.8 kilograms of {sup 235}U. While most reactors attempt to minimize the escape of neutrons from the core, the HFBR`s D{sub 2}O design allows the thermal neutron flux to peak in the reflector region and maximizes the number of thermal neutrons available to nine horizontal external beams, H-1 to H-9, used for neutron scattering and capture reactions, supporting physics, chemistry and biology experiments. All horizontal beam tubes were built tangential to the direction of the emerging neutrons, except for the H-2 beam tube, which looks directly at the core and has been used for neutron cross section measurements utilizing fast neutrons and for the TRISTAN fission product studies. In recent years, there have been some beam modifications and new instrumentation introduced at the HFBR. A high resolution neutron powder diffractometer instrument is now operating with a resolution of 5 {times} 10{sup {minus}4} at horizontal beam line H-1. To study scattering from liquid surfaces, a neutron reflection spectrometer was introduced on the CNF beam line at H-9. In the past year, a fourth beam line has been added to the CNF line at H-9. The existing beam plug at the H-6 beam line has recently been removed and a new plug, which will feature super mirrored surfaces, is now being installed. Last year, the vertical beam thimble, V-13, a fixed port filled with thirty year old samples used for HFBR material surveillance studies was replaced by a new thimble and charging station at the core edge creating an irradiation facility to substitute for the original V-13. A neutron dosimetry program has begun to measure and calculate the energy dependent neutron and gamma ray flux densities and/or dose rates at horizontal beam lines and vertical irradiation thimbles.

  15. The Department of Energy's National Security Information Fundamental

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

    Classification Guidance Review | Department of Energy The Department of Energy's National Security Information Fundamental Classification Guidance Review The Department of Energy's National Security Information Fundamental Classification Guidance Review The goals of this review process was to evaluate the guidance content, determine if the guidance conforms to current operational and technical circumstances, determine if the guidance meets the standards for classification under section 1.4

  16. Fundamental Interactions | U.S. DOE Office of Science (SC)

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

    Fundamental Interactions Chemical Sciences, Geosciences, & Biosciences (CSGB) Division CSGB Home About Research Areas Energy Frontier Research Centers (EFRCs) DOE Energy Innovation Hubs Reports and Activities Science Highlights Principal Investigators' Meetings BES Home Research Areas Fundamental Interactions Print Text Size: A A A FeedbackShare Page Research emphasis is placed on structural and dynamical studies of atoms, molecules, and nanostructures, and the description of their

  17. DOE Fundamentals Handbook: Instrumentation and Control, Volume 2

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Instrumentation and Control Fundamentals Handbook personnel, and the technical staff facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of instrumentation and control systems. The handbook includes information on temperature, pressure, flow, and level detection systems; position indication systems; process control systems; and radiation detection principles. This information will provide personnel with an understanding of the basic operation of various types of DOE nuclear facility instrumentation and control systems.

  18. Fuel-Cell Fundamentals at Low and Subzero Temperatures

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

    Cell Fundamentals at Low and Subzero Temperatures Adam Z. Weber (PI), John Newman, Clayton Radke LBNL Rangachary Mukundan, Rodney Borup LANL Michael Perry UTRC Mark Debe 3M Chao-Yang Wang PSU This presentation does not contain any proprietary or confidential information Objectives  Fundamental understanding of transport phenomena and water and thermal management at low and subzero temperatures using state-of-the-art materials  Enable optimization strategies to be developed to overcome

  19. Fundamental Study of the Mechanical Strength Degradation Mechanisms of PFSA

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

    Membranes and MEAs | Department of Energy Fundamental Study of the Mechanical Strength Degradation Mechanisms of PFSA Membranes and MEAs Fundamental Study of the Mechanical Strength Degradation Mechanisms of PFSA Membranes and MEAs Presentation at the 2008 High Temperature Membrane Working Group Meeting held June 9, 2008, in Washington, DC huang_htmwg_2008.pdf (2.27 MB) More Documents & Publications Membrane Durability in PEM Fuel Cells: Chemical Degradation Automotive Perspective on PEM

  20. Fundamental Mechanisms of Transient States in Materials Quantified by DTEM

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

    Geoffrey Campbell is the Principal Investigator for Fundamental Mechanisms of Transient States in Materials Quantified by DTEM. Fundamental Mechanisms of Transient States in Materials Quantified by DTEM Research We study the coupled dynamics of phase transformation nucleation and growth, microstructure, and thermodynamics in nanoscale systems evolving on nanosecond to microsecond time scales using time resolved in situ microscopy (and other) techniques. DTEM enables in situ characterization of

  1. Weatherization Installer/Technician Fundamentals 2.0 - Moisture Barriers |

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

    Department of Energy Moisture Barriers Weatherization Installer/Technician Fundamentals 2.0 - Moisture Barriers Moisture Barriers - Complete (2.34 MB) Lesson Plan: Moisture Barriers (107.22 KB) PowerPoint: Moisture Barriers (2.31 MB) More Documents & Publications Energy Auditor - Single Family 2.0: Moisture Assessment Weatherization Installer/Technician Fundamentals 2.0 - Roofing, Flashing, and Attic Ventilation Installation Needs Energy Auditor - Single Family 2.0: Building Shell

  2. Project Profile: Fundamental Corrosion Studies in High-Temperature Molten

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

    Salt Systems for Next-Generation CSP Systems | Department of Energy Fundamental Corrosion Studies in High-Temperature Molten Salt Systems for Next-Generation CSP Systems Project Profile: Fundamental Corrosion Studies in High-Temperature Molten Salt Systems for Next-Generation CSP Systems Savannah River National Laboratory logo -- This project is inactive -- The Savannah River National Laboratory (SRNL), under the National Laboratory R&D competitive funding opportunity, is working with

  3. DOE Fundamentals Handbook: Instrumentation and Control, Volume 1

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Instrumentation and Control Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of instrumentation and control systems. The handbook includes information on temperature, pressure, flow, and level detection systems; position indication systems; process control systems; and radiation detection principles. This information will provide personnel with an understanding of the basic operation of various types of DOE nuclear facility instrumentation and control systems.

  4. Advancing the Fundamental Understanding of Fission: 2014 LDRD 20120077DR

    Office of Scientific and Technical Information (OSTI)

    Review (Technical Report) | SciTech Connect Advancing the Fundamental Understanding of Fission: 2014 LDRD 20120077DR Review Citation Details In-Document Search Title: Advancing the Fundamental Understanding of Fission: 2014 LDRD 20120077DR Review The following slides were presented as part of the LDRD 20120077DR Progress Appraisal Review held Tuesday, February 4, 2014. This is part of an ongoing project assessment the previous of which was documented in LA-UR-13-21182. This presentation

  5. MCViNE- An object oriented Monte Carlo neutron ray tracing simulation package

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

    Lin, J. Y. Y.; Smith, Hillary L.; Granroth, Garrett E.; Abernathy, Douglas L.; Lumsden, Mark D.; Winn, Barry L.; Aczel, Adam A.; Aivazis, Michael; Fultz, Brent

    2015-11-28

    MCViNE (Monte-Carlo VIrtual Neutron Experiment) is an open-source Monte Carlo (MC) neutron ray-tracing software for performing computer modeling and simulations that mirror real neutron scattering experiments. We exploited the close similarity between how instrument components are designed and operated and how such components can be modeled in software. For example we used object oriented programming concepts for representing neutron scatterers and detector systems, and recursive algorithms for implementing multiple scattering. Combining these features together in MCViNE allows one to handle sophisticated neutron scattering problems in modern instruments, including, for example, neutron detection by complex detector systems, and single and multiplemore » scattering events in a variety of samples and sample environments. In addition, MCViNE can use simulation components from linear-chain-based MC ray tracing packages which facilitates porting instrument models from those codes. Furthermore it allows for components written solely in Python, which expedites prototyping of new components. These developments have enabled detailed simulations of neutron scattering experiments, with non-trivial samples, for time-of-flight inelastic instruments at the Spallation Neutron Source. Examples of such simulations for powder and single-crystal samples with various scattering kernels, including kernels for phonon and magnon scattering, are presented. As a result, with simulations that closely reproduce experimental results, scattering mechanisms can be turned on and off to determine how they contribute to the measured scattering intensities, improving our understanding of the underlying physics.« less

  6. MCViNE- An object oriented Monte Carlo neutron ray tracing simulation package

    SciTech Connect (OSTI)

    Lin, J. Y. Y.; Smith, Hillary L.; Granroth, Garrett E.; Abernathy, Douglas L.; Lumsden, Mark D.; Winn, Barry L.; Aczel, Adam A.; Aivazis, Michael; Fultz, Brent

    2015-11-28

    MCViNE (Monte-Carlo VIrtual Neutron Experiment) is an open-source Monte Carlo (MC) neutron ray-tracing software for performing computer modeling and simulations that mirror real neutron scattering experiments. We exploited the close similarity between how instrument components are designed and operated and how such components can be modeled in software. For example we used object oriented programming concepts for representing neutron scatterers and detector systems, and recursive algorithms for implementing multiple scattering. Combining these features together in MCViNE allows one to handle sophisticated neutron scattering problems in modern instruments, including, for example, neutron detection by complex detector systems, and single and multiple scattering events in a variety of samples and sample environments. In addition, MCViNE can use simulation components from linear-chain-based MC ray tracing packages which facilitates porting instrument models from those codes. Furthermore it allows for components written solely in Python, which expedites prototyping of new components. These developments have enabled detailed simulations of neutron scattering experiments, with non-trivial samples, for time-of-flight inelastic instruments at the Spallation Neutron Source. Examples of such simulations for powder and single-crystal samples with various scattering kernels, including kernels for phonon and magnon scattering, are presented. As a result, with simulations that closely reproduce experimental results, scattering mechanisms can be turned on and off to determine how they contribute to the measured scattering intensities, improving our understanding of the underlying physics.

  7. Sandia National Laboratories: Careers: Physics

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

    Physics Water droplets photo Physicists from all research backgrounds are helping Sandia solve the world's toughest challenges. There is no "typical" career for a physicist at Sandia. Instead, Sandia offers physicists a multitude of opportunities to participate in multidisciplinary teams on projects ranging from groundbreaking fundamental research to influential national security applications. Whatever the project, physicists are making important contributions to Sandia's missions in

  8. Inquiring Minds - Questions About Physics

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

    Concept of ether in explaining forces You asked: Will there be any research carried out in the near or distant future to find a physical relationship between gravity, mass, light, matter/antimatter through something like the idea of ether hundred years ago? The concept of ether surfaced decades before scientists knew of quantum mechanics and some very fundamental symmetry principles of the microscopic world. Because of the huge change in knowledge, the historic word ether is not used anymore

  9. High energy neutron Computed Tomography developed

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

    High energy neutron Computed Tomography developed High energy neutron Computed Tomography developed LANSCE now has a high-energy neutron imaging capability that can be deployed on WNR flight paths for unclassified and classified objects. May 9, 2014 Neutron tomography horizontal "slice" of a tungsten and polyethylene test object containing tungsten carbide BBs. Neutron tomography horizontal "slice" of a tungsten and polyethylene test object containing tungsten carbide BBs.

  10. Crystals for neutron scattering studies of quantum magnetism

    SciTech Connect (OSTI)

    Yankova, Tantiana; Hüvonen, Dan; Mühlbauer, Sebastian; Schmidiger, David; Wulf, Erik; Hong, Tao; Garlea, Vasile O; Custelcean, Radu; Ehlers, Georg

    2012-01-01

    We review a strategy for targeted synthesis of large single crystal samples of prototype quantum magnets for inelastic neutron scattering experiments. Four case studies of organic copper halogenide S = 1/2 systems are presented. They are meant to illustrate that exciting experimental results pertaining to the forefront of many-body quantum physics can be obtained on samples grown using very simple techniques, standard laboratory equipment, and almost no experience in advanced crystal growth techniques.

  11. Bertram Brockhouse, the Triple-axis Spectrometer, and Neutron Spectroscopy

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

    Bertram Brockhouse, the Triple-axis Spectrometer, and Neutron Spectroscopy Resources with Additional Information Bertram Brockhouse Courtesy of McMaster University Bertram Brockhouse 'attended the University of British Columbia, from which he graduated in 1947 with first class honours in mathematics and physics. He entered the University of Toronto that same year ... . He obtained his Ph.D. in 1950, with a thesis entitled "The Effect of Stress and Temperature upon the Magnetic Properties of

  12. Portable Neutron Sensors for Emergency Response Operations

    SciTech Connect (OSTI)

    ,

    2012-06-24

    This article presents the experimental work performed in the area of neutron detector development at the Remote Sensing Laboratory–Andrews Operations (RSL-AO) sponsored by the U.S. Department of Energy, National Nuclear Security Administration (NNSA) in the last four years. During the 1950s neutron detectors were developed mostly to characterize nuclear reactors where the neutron flux is high. Due to the indirect nature of neutron detection via interaction with other particles, neutron counting and neutron energy measurements have never been as precise as gamma-ray counting measurements and gamma-ray spectroscopy. This indirect nature is intrinsic to all neutron measurement endeavors (except perhaps for neutron spin-related experiments, viz. neutron spin-echo measurements where one obtains μeV energy resolution). In emergency response situations generally the count rates are low, and neutrons may be scattered around in inhomogeneous intervening materials. It is also true that neutron sensors are most efficient for the lowest energy neutrons, so it is not as easy to detect and count energetic neutrons. Most of the emergency response neutron detectors are offshoots of nuclear device diagnostics tools and special nuclear materials characterization equipment, because that is what is available commercially. These instruments mostly are laboratory equipment, and not field-deployable gear suited for mobile teams. Our goal is to design and prototype field-deployable, ruggedized, lightweight, efficient neutron detectors.

  13. Theoretical perspectives on strange physics

    SciTech Connect (OSTI)

    Ellis, J.

    1983-04-01

    Kaons are heavy enough to have an interesting range of decay modes available to them, and light enough to be produced in sufficient numbers to explore rare modes with satisfying statistics. Kaons and their decays have provided at least two major breakthroughs in our knowledge of fundamental physics. They have revealed to us CP violation, and their lack of flavor-changing neutral interactions warned us to expect charm. In addition, K/sup 0/-anti K/sup 0/ mixing has provided us with one of our most elegant and sensitive laboratories for testing quantum mechanics. There is every reason to expect that future generations of kaon experiments with intense sources would add further to our knowledge of fundamental physics. This talk attempts to set future kaon experiments in a general theoretical context, and indicate how they may bear upon fundamental theoretical issues. A survey of different experiments which would be done with an Intense Medium Energy Source of Strangeness, including rare K decays, probes of the nature of CP isolation, ..mu.. decays, hyperon decays and neutrino physics is given. (WHK)

  14. Ion chamber based neutron detectors

    DOE Patents [OSTI]

    Derzon, Mark S; Galambos, Paul C; Renzi, Ronald F

    2014-12-16

    A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

  15. DETERMINATION OF SPECIFIC NEUTRONIC REACTIVITY

    DOE Patents [OSTI]

    Dessauer, G.

    1960-05-10

    A method is given for production-line determination of the specific neutronic reactivity of such objects as individual nuclear fuel or neutron absorber elements and is notable for rapidity and apparatus simplicity. The object is incorporated in a slightly sub-critical chain fission reactive assembly having a discrete neutron source, thereby establishing a K/sub eff/ within the crucial range of 0.95 to 0.995. The range was found to afford, uniquely, flux- transient damped response in a niatter of seconds simultaneously with acceptable analytical sensitivity. The resulting neutron flux measured at a situs spaced from both object and source within the assembly serves as a calibrable indication of said reactivity.

  16. Fundamental investigation of Duct/ESP phenomena: 1. 7 MW pilot parametric testing results

    SciTech Connect (OSTI)

    McGuire, L.M.; Brown, C.A.

    1991-07-22

    Radian Corporation was contracted to investigate duct injection and electrostatic precipitator phenomena in a 1.7-MW pilot plant constructed for this test program. This study was an attempt to resolve previous problems and to answer remaining questions with the technology using an approach which concentrated on the fundamental mechanisms of the process. The goal of the study was to obtain a better understanding of the basic physical and chemical phenomena that control: (1) the desulfurization of flue gas by calcium-based reagent, and (2) the coupling of the duct injection process to an existing ESP particulate collection device. (VC)

  17. CONTROL MEANS FOR NEUTRONIC REACTORS

    DOE Patents [OSTI]

    Tonks, L.

    1962-08-01

    A control device surrounding the active portion of a nuclear reactor is described. The control device consists of a plurality of contiguous cylinders partly filled with a neutron absorbing material and partly filled with a neutron reflecting material, each cylinder having a longitudinal reentrant surface into which a portion of an adjacent cylinder extends, one of the cylinders having two re-entrant surfaces, and means for rotating the cylinders one at a time. (AEC)

  18. SETTABLE NEUTRON RADIATION SHIELDING MATERIAL

    DOE Patents [OSTI]

    Axelrad, I.R.

    1960-11-22

    A settable, viscous, putty-like shielding composition is described. It consists of an intimate admixture of a major proportion of a compound having a ratio of hydrogen atoms to all other atoms therein within the range of from 0.5: 1 to 2:l. from 0.5 to 10% by weight of boron, and a fluid resinous carrier This composition when cured is adapted to attenuate fast moving neutrons and capture slow moving neutrons.

  19. Alternative Neutron Detection Testing Summary

    SciTech Connect (OSTI)

    Kouzes, Richard T.; Ely, James H.; Erikson, Luke E.; Kernan, Warnick J.; Lintereur, Azaree T.; Siciliano, Edward R.; Stromswold, David C.; Woodring, Mitchell L.

    2010-04-08

    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. Most currently deployed radiation portal monitors (RPMs) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large area neutron detector. This type of neutron detector is used in the TSA and other RPMs installed in international locations and in the Ludlum and Science Applications International Corporation RPMs deployed primarily for domestic applications. 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. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. These technologies are: 1) Boron trifluoride-filled proportional counters, 2) Boron-lined proportional counters, 3) Lithium-loaded glass fibers, and 4) Coated wavelength-shifting plastic fibers. Reported here is a summary of the testing carried out at Pacific Northwest National Laboratory on these technologies to date, as well as measurements on 3He tubes at various pressures. Details on these measurements are available in the referenced reports. Sponsors of these tests include the Department of Energy (DOE), Department of Homeland Security (DHS), and the Department of Defense (DoD), as well as internal Pacific Northwest National Laboratory funds.

  20. Neutron detectors comprising boron powder

    DOE Patents [OSTI]

    Wang, Zhehui; Morris, Christopher; Bacon, Jeffrey Darnell; Makela, Mark F; Spaulding, Randy Jay

    2013-05-21

    High-efficiency neutron detector substrate assemblies comprising a first conductive substrate, wherein a first side of the substrate is in direct contact with a first layer of a powder material comprising .sup.10boron, .sup.10boron carbide or combinations thereof, and wherein a conductive material is in proximity to the first layer of powder material; and processes of making said neutron detector substrate assemblies.

  1. J lich Neutron Spin Echo Instrument Inaugurated (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    J lich Neutron Spin Echo Instrument Inaugurated Citation Details In-Document Search Title: J lich Neutron Spin Echo Instrument Inaugurated The neutron spin echo (NSE) spectrometer ...

  2. DOE Science Showcase - Neutron Science Research from DOE Databases...

    Office of Scientific and Technical Information (OSTI)

    Neutron Science Research from DOE Databases Additional neutron science research in DOE Databases Information Bridge Neutron scattering research was pioneered in 1946 by ORNL's ...

  3. NUCLEAR ENERGY UNIVERSITY PROGRAMS Improved Fission Neutron Data...

    National Nuclear Security Administration (NNSA)

    NUCLEAR ENERGY UNIVERSITY PROGRAMS Improved Fission Neutron Data Base for Active ... the detection of neutrons from fission induced by fast neutrons or high-energy gamma rays. ...

  4. Measuring and monitoring KIPT Neutron Source Facility Reactivity

    SciTech Connect (OSTI)

    Cao, Yan; Gohar, Yousry; Zhong, Zhaopeng

    2015-08-01

    Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on developing and constructing a neutron source facility at Kharkov, Ukraine. The facility consists of an accelerator-driven subcritical system. The accelerator has a 100 kW electron beam using 100 MeV electrons. The subcritical assembly has keff less than 0.98. To ensure the safe operation of this neutron source facility, the reactivity of the subcritical core has to be accurately determined and continuously monitored. A technique which combines the area-ratio method and the flux-to-current ratio method is purposed to determine the reactivity of the KIPT subcritical assembly at various conditions. In particular, the area-ratio method can determine the absolute reactivity of the subcritical assembly in units of dollars by performing pulsed-neutron experiments. It provides reference reactivities for the flux-to-current ratio method to track and monitor the reactivity deviations from the reference state while the facility is at other operation modes. Monte Carlo simulations are performed to simulate both methods using the numerical model of the KIPT subcritical assembly. It is found that the reactivities obtained from both the area-ratio method and the flux-to-current ratio method are spatially dependent on the neutron detector locations and types. Numerical simulations also suggest optimal neutron detector locations to minimize the spatial effects in the flux-to-current ratio method. The spatial correction factors are calculated using Monte Carlo methods for both measuring methods at the selected neutron detector locations. Monte Carlo simulations are also performed to verify the accuracy of the flux-to-current ratio method in monitoring the reactivity swing during a fuel burnup cycle.

  5. The EOS of neutron matter, and the effect of Lambda hyperons to neutron star structure

    SciTech Connect (OSTI)

    Gandolfi, Stefano

    2015-01-13

    The following topics are addressed: the model and the method; equation of state of neutron matter, role of three-neutron force; symmetry energy; ?-hypernuclei; ?-neutron matter; and neutron star structure. In summary, quantum Monte Carlo methods are useful to study nuclear systems in a coherent framework; the three-neutron force is the bridge between Esym and neutron star structure; and neutron star observations are becoming competitive with experiments. ?-nucleon data are very limited, but ?NN is very important. The role of ? in neutron stars is far from understood; more ?N data are needed. The author's conclusion: We cannot conclude anything with present models.

  6. Lighting fundamentals handbook: Lighting fundamentals and principles for utility personnel. Final report

    SciTech Connect (OSTI)

    Eley, C.; Tolen, T.; Benya, J.R.

    1992-12-01

    Lighting accounts for approximately 30% of overall electricity use and demand in commercial buildings. This handbook for utility personnel provides a source of basic information on lighting principles, lighting equipment, and other considerations related to lighting design. The handbook is divided into three parts. Part One, Physics of Light, has chapters on light, vision, optics, and photometry. Part Two, Lighting Equipment and Technology, focuses on lamps, luminaires, and lighting controls. Part Three, Lighting Design Decisions, deals with the manner in which lighting design decisions are made and reviews relevant methods and issues. These include the quantity and quality of light needed for visual tasks, calculation methods for verifying that lighting needs are satisfied, lighting economics and methods for evaluating investments in efficient lighting systems, and miscellaneous design issues including energy codes, power quality, photobiology, and disposal of lighting equipment. The handbook contains a discussion of the role of the utility in promoting the use of energy-efficient lighting. The handbook also includes a lighting glossary and a list of references for additional information. This convenient and comprehensive handbook is designed to enable utility lighting personnel to assist their customers in developing high-quality, energy-efficient lighting systems. The handbook is not intended to be an up-to-date reference on lighting products and equipment.

  7. Neutron and X-ray Detectors

    SciTech Connect (OSTI)

    Carini, Gabriella; Denes, Peter; Gruener, Sol; Lessner, Elianne

    2012-08-01

    (and two computing hurdles that result from the corresponding increase in data volume) for the detector community to overcome in order to realize the full potential of BES neutron and X-ray facilities. Resolving these detector impediments will improve scientific productivity both by enabling new types of experiments, which will expand the scientific breadth at the X-ray and neutron facilities, and by potentially reducing the beam time required for a given experiment. These research priorities are summarized in the table below. Note that multiple, simultaneous detector improvements are often required to take full advantage of brighter sources. High-efficiency hard X-ray sensors: The fraction of incident particles that are actually detected defines detector efficiency. Silicon, the most common direct-detection X-ray sensor material, is (for typical sensor thicknesses) 100% efficient at 8 keV, 25%efficient at 20 keV, and only 3% efficient at 50 keV. Other materials are needed for hard X-rays. Replacement for 3He for neutron detectors: 3He has long been the neutron detection medium of choice because of its high cross section over a wide neutron energy range for the reaction 3He + n —> 3H + 1H + 0.764 MeV. 3He stockpiles are rapidly dwindling, and what is available can be had only at prohibitively high prices. Doped scintillators hold promise as ways to capture neutrons and convert them into light, although work is needed on brighter, more efficient scintillator solutions. Neutron detectors also require advances in speed and resolution. Fast-framing X-ray detectors: Today’s brighter X-ray sources make time-resolved studies possible. For example, hybrid X-ray pixel detectors, initially developed for particle physics, are becoming fairly mature X-ray detectors, with considerable development in Europe. To truly enable time-resolved studies, higher frame rates and dynamic range are required, and smaller pixel sizes are desirable. High-speed spectroscopic X-ray detectors

  8. Physical Scientist

    Broader source: Energy.gov [DOE]

    The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, providing more than 40 percent of total funding for this vital area of...

  9. Subatomic Physics

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

    5 Subatomic Physics We play a major role in large-scale scientific collaborations around the world, performing nuclear physics experiments that advance the understanding of the hidden subatomic reactions of the universe and how high explosives affect matter. Contact Us Group Leader Melynda Brooks Email Deputy Group Leader Frans Trouw Email Group Office (505) 667-6941 A detector that uses muons, tiny particles generated when cosmic rays interact with Earth's atmosphere to look inside the cores of

  10. Protons Hog the Momentum in Neutron-Rich Nuclei | U.S. DOE Office of

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

    Science (SC) Protons Hog the Momentum in Neutron-Rich Nuclei Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science Advisory Committee (NSAC) Community Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: Email Us More Information » 05.01.15 Protons Hog the Momentum in Neutron-Rich Nuclei

  11. Solution-grown crystals for neutron radiation detectors, and methods of solution growth

    DOE Patents [OSTI]

    Zaitseva, Natalia; Carman, M Leslie; Payne, Steve

    2014-10-28

    An organic crystal according to one embodiment includes an organic crystal comprising diphenylacetylene and stilbene or a stilbene derivative, the crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source. A system according to one embodiment includes an organic crystal comprising diphenylacetylene and stilbene or a stilbene derivative, the crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source; and a photodetector for detecting the signal response of the organic crystal. Methods of making such crystals are also provided.

  12. Neutron Star Science with the NuSTAR

    SciTech Connect (OSTI)

    Vogel, J. K.

    2015-10-16

    The Nuclear Spectroscopic Telescope Array (NuSTAR), launched in June 2012, helped scientists obtain for the first time a sensitive high-­energy X-­ray map of the sky with extraordinary resolution. This pioneering telescope has aided in the understanding of how stars explode and neutron stars are born. LLNL is a founding member of the NuSTAR project, with key personnel on its optics and science team. We used NuSTAR to observe and analyze the observations of different neutron star classes identified in the last decade that are still poorly understood. These studies not only help to comprehend newly discovered astrophysical phenomena and emission processes for members of the neutron star family, but also expand the utility of such observations for addressing broader questions in astrophysics and other physics disciplines. For example, neutron stars provide an excellent laboratory to study exotic and extreme phenomena, such as the equation of state of the densest matter known, the behavior of matter in extreme magnetic fields, and the effects of general relativity. At the same time, knowing their accurate populations has profound implications for understanding the life cycle of massive stars, star collapse, and overall galactic evolution.

  13. Time reversal invariance - a test in free neutron decay

    SciTech Connect (OSTI)

    Lising, Laura J.

    1999-05-18

    Time reversal invariance violation plays only a small role in the Standard Model, and the existence of a T-violating effect above the predicted level would be an indication of new physics. A sensitive probe of this symmetry in the weak interaction is the measurement of the T-violating ''D''-correlation in the decay of free neutrons. The triple-correlation D{sigma}{sub n}{center_dot}p{sub e} x p{sub v} involves three kinematic variables, the neutron spin, electron momentu, and neutrino (or proton) momentum, and changes sign under time reversal. This experiment detects the decay products of a polarized cold neutron beam with an octagonal array of scintillation and solid-state detectors. Data from first run at NIST's Cold Neutron Research Facility give a D-coefficient of -0.1 {+-} 1.3(stat.) {+-} 0.7(syst) x 10{sup -3}. This measurement has the greatest bearing on extensions to the Standard model that incorporate leptoquarks, although exotic fermion and lift-right symmetric models also allow a D as large as the present limit.

  14. A New Polyethylene Scattering Law Determined Using Inelastic Neutron Scattering

    SciTech Connect (OSTI)

    Lavelle, Christopher M [ORNL; Liu, C [Oak Ridge National Laboratory (ORNL); Stone, Matthew B [ORNL

    2013-01-01

    Monte Carlo neutron transport codes such as MCNP rely on accurate data for nuclear physics cross-sections to produce accurate results. At low energy, this takes the form of scattering laws based on the dynamic structure factor, S (Q, E). High density polyethylene (HDPE) is frequently employed as a neutron moderator at both high and low temperatures, however the only cross-sections available are for T =300 K, and the evaluation has not been updated in quite some time. In this paper we describe inelastic neutron scattering measurements on HDPE at 5 and 300 K which are used to improve the scattering law for HDPE. We describe the experimental methods, review some of the past HDPE scattering laws, and compare computations using these models to the measured S (Q, E). The total cross-section is compared to available data, and the treatment of the carbon secondary scatterer as a free gas is assessed. We also discuss the use of the measurement itself as a scattering law via the 1 phonon approximation. We show that a scattering law computed using a more detailed model for the Generalized Density of States (GDOS) compares more favorably to this experiment, suggesting that inelastic neutron scattering can play an important role in both the development and validation of new scattering laws for Monte Carlo work.

  15. Probing exotic physics with cosmic neutrinos

    SciTech Connect (OSTI)

    Hooper, Dan; /Fermilab

    2005-10-01

    Traditionally, collider experiments have been the primary tool used in searching for particle physics beyond the Standard Model. In this talk, I will discuss alternative approaches for exploring exotic physics scenarios using high energy and ultra-high energy cosmic neutrinos. Such neutrinos can be used to study interactions at energies higher, and over baselines longer, than those accessible to colliders. In this way, neutrino astronomy can provide a window into fundamental physics which is highly complementary to collider techniques. I will discuss the role of neutrino astronomy in fundamental physics, considering the use of such techniques in studying several specific scenarios including low scale gravity models, Standard Model electroweak instanton induced interactions, decaying neutrinos and quantum decoherence.

  16. 2013 Review of Neutron and Non-Neutron Nuclear Data

    SciTech Connect (OSTI)

    Holden, N. E.

    2014-05-23

    The results of a review and evaluation of neutron and non-neutron nuclear data published in the scientific literature over the past three years since the ISRD-14 Symposium has been performed and the highlights are presented. Included in the data review are the status of new chemical elements, new measurements of the isotopic composition for many chemical elements and the resulting change in the atomic weight values. New half-life measurements for both short-lived and longlived nuclides, some alpha decay and double beta decay measurements for quasistable nuclides are discussed. The latest evaluation of atomic masses has been published. Data from new measurements on the very heavy (trans-meitnerium) elements are discussed and tabulated. Data on various recent neutron cross section and resonance integral measurements are discussed and tabulated.

  17. Neutronic fuel element fabrication

    DOE Patents [OSTI]

    Korton, George

    2004-02-24

    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

  18. BF3 Neutron Detector Tests

    SciTech Connect (OSTI)

    Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T.; Siciliano, Edward R.; Woodring, Mitchell L.

    2009-12-09

    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; thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and detection capabilities are being investigated. Reported here are the results of tests of the efficiency of BF3 tubes at a pressure of 800 torr. These measurements were made partially to validate models of the RPM system that have been modified to simulate the performance of BF3-filled tubes. While BF3 could be a potential replacement for 3He, there are limitations to its use in deployed systems.

  19. Neutron coincidence measurements when nuclear parameters vary during the multiplication process

    SciTech Connect (OSTI)

    Lu, Ming-Shih; Teichmann, T.

    1995-07-01

    In a recent paper, a physical/mathematical model was developed for neutron coincidence counting, taking explicit account of neutron absorption and leakage, and using dual probability generating function to derive explicit formulae for the single and multiple count-rates in terms of the physical parameters of the system. The results of this modeling proved very successful in a number of cases in which the system parameters (neutron reaction cross-sections, detection probabilities, etc.) remained the same at the various stages of the process (i.e. from collision to collision). However, there are practical circumstances in which such system parameters change from collision to collision, and it is necessary to accommodate these, too, in a general theory, applicable to such situations. For instance, in the case of the neutron coincidence collar (NCC), the parameters for the initial, spontaneous fission neutrons, are not the same as those for the succeeding induced fission neutrons, and similar situations can be envisaged for certain other experimental configurations. This present document shows how the previous considerations can be elaborated to embrace these more general requirements.

  20. Saturday Morning Physics talk (Feb 2013)

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

    with trapped atoms and ions 2/2/2013 Dan Melconian 2/2/2013 Dan Melconian Outline * Scope and applications of nuclear physics  precision frontier compliments LHC  properties of nuclei used to explain celestial phenomena and conditions just after the Big Bang  diagnostic and therapeutic medicine * "Cool" tools - atom traps  probing fundamental symmetries  (ion traps)  trace analysis and aquifers in the Sahara 2/2/2013 Dan Melconian What is Nuclear Physics? * Began