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1

Thermophysical properties of saturated light and heavy water for advanced neutron source applications  

SciTech Connect (OSTI)

The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor's nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300[degrees]C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250[degrees]C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

Crabtree, A.; Siman-Tov, M.

1993-05-01T23:59:59.000Z

2

Thermophysical properties of saturated light and heavy water for Advanced Neutron Source applications  

SciTech Connect (OSTI)

The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor`s nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300{degrees}C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250{degrees}C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

Crabtree, A.; Siman-Tov, M.

1993-05-01T23:59:59.000Z

3

Spallation Neutron Source, SNS  

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

Spallation Neutron Source Spallation Neutron Source Providing the most intense pulsed neutron beams in the world... Accumulator Ring Commissioning Latest Step for Spallation Neutron Source The Spallation Neutron Source, located at Oak Ridge National Laboratory, has passed another milestone on the way to completion this year--the commissioning of the proton accumulator ring. Brookhaven led the design and construction of the accumulator ring, which will allow an order of magnitude more beam power than any other facility in the world. The Spallation Neutron Source (SNS) is an accelerator-based neutron source being built in Oak Ridge, Tennessee, by the U.S. Department of Energy. The figure on the right shows a schematic of the accumulator ring and transport beam lines that are being designed and built by Brookhaven

4

Neutron sources and applications  

SciTech Connect (OSTI)

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

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

1994-01-01T23:59:59.000Z

5

Spallation Neutron Source  

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

D/gim D/gim Spallation Neutron Source SNS is an accelerator-based neutron source. This one-of-a-kind facility pro- vides the most intense pulsed neutron beams in the world. When ramped up to its full beam power of 1.4 MW, SNS will be eight times more powerful than today's best facility. It will give researchers more detailed snapshots of the smallest samples of physical and biological materials than ever before

6

Stanford Synchrotron Radiation Light Source (SSRL) | U.S. DOE...  

Office of Science (SC) Website

Syncrotron Light Source (NSLS-II) Stanford Synchrotron Radiation Light Source (SSRL) Neutron Scattering Facilities Nanoscale Science Research Centers (NSRCs) Projects...

7

Spallation Neutron Source | ORNL Neutron Sciences  

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

Spallation Neutron Source SNS site, Spring 2012 The 80-acre SNS site is located on the east end of the ORNL campus and is about a three-minute drive from her sister neutron...

8

Optimization of neutron source  

SciTech Connect (OSTI)

I consider here the optimization of the two component neutron source, allowing beam species and energy to vary. A simple model is developed, based on the earlier publications, that permits the optimum to be obtained simply. The two component plasma, with one species of hot ion (D{sup +} or T{sup +}) and the complementary species of cold ion, is easy to analyze in the case of a spatially uniform cold plasma, as to good approximation the total number of hot ions is important but not their spatial distribution. Consequently, the optimization can ignore spatial effects. The problem of a plasma with both types of hot ions and cold ions is rather more difficult, as the neutron production by hot-hot interactions is sensitive to their spatial distributions. Consequently, consideration of this problem will be delayed to a future memorandum. The basic model is that used in the published articles on the two-component, beam-plasma mirror source. I integrate the Fokker-Planck equation analytically, obtaining good agreement with previous numerical results. This simplifies the optimization, by providing a functional form for the neutron production. The primary result is expressed in terms of the power efficiency: watts of neutrons/watts of primary power. The latter includes the positive ion neutralization efficiency. At 150 keV, the present model obtains an efficiency of 0.66%, compared with 0.53% of the earlier calculation.

Hooper, E.B.

1993-11-09T23:59:59.000Z

9

National Synchrotron Light Source  

ScienceCinema (OSTI)

A tour of Brookhaven's National Synchrotron Light Source (NSLS), hosted by Associate Laboratory Director for Light Sources, Stephen Dierker. The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, environmental, and materials sciences.

BNL

2009-09-01T23:59:59.000Z

10

Neutron Generator as a Neutron Source for BNCT  

Science Journals Connector (OSTI)

A neutron generator was investigated for a neutron source for BNCT. Neutron generators have some obvious advantages over nuclear reactors for this purpose. The neutron source is the reaction D(d,n)3He. Moderation...

Gad Shani; Lev Tsvang; Semion Rozin; Michael Quastel

1996-01-01T23:59:59.000Z

11

SNS | Spallation Neutron Source | ORNL  

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

SNS SNS Instruments Working with SNS Contact Us User Program Manager Laura Morris Edwards 865.574.2966 Spallation Neutron Source Home | User Facilities | SNS SNS | Spallation Neutron Source SHARE SNS is an accelerator-based neutron source in Oak Ridge, Tennessee, USA. This one-of-a-kind facility provides the most intense pulsed neutron beams in the world for scientific research and industrial development. The 80-acre SNS site is located on Chestnut Ridge and is part of Oak Ridge National Laboratory. Although most people don't know it, neutron scattering research has a lot to do with our everyday lives. For example, things like medicine, food, electronics, and cars and airplanes have all been improved by neutron scattering research. Neutron research also helps scientists improve materials used in a

12

Fusion pumped light source  

DOE Patents [OSTI]

Apparatus is provided for generating energy in the form of light radiation. A fusion reactor is provided for generating a long, or continuous, pulse of high-energy neutrons. The neutron flux is coupled directly with the lasing medium. The lasing medium includes a first component selected from Group O of the periodic table of the elements and having a high inelastic scattering cross section. Gamma radiation from the inelastic scattering reactions interacts with the first component to excite the first component, which decays by photon emission at a first output wavelength. The first output wavelength may be shifted to a second output wavelength using a second liquid component responsive to the first output wavelength. The light outputs may be converted to a coherent laser output by incorporating conventional optics adjacent the laser medium.

Pappas, Daniel S. (Los Alamos, NM)

1989-01-01T23:59:59.000Z

13

National Synchrotron Light Source  

ScienceCinema (OSTI)

A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

None

2010-01-08T23:59:59.000Z

14

Neutron producing target for accelerator based neutron source for  

E-Print Network [OSTI]

247 Neutron producing target for accelerator based neutron source for NCT V. Belov1 , S. Fadeev1, Russia Summary Neutron producing targets for novel accelerator based neutron source [1, 2] are presented Neutron producing target is one of the main elements of proposed accelerator based facility for neutron

Taskaev, Sergey Yur'evich

15

National Synchrotron Light Source  

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

Environmental Assessment Environmental Assessment Proposed Upgrade and Improvement of the National Synchrotron Light Source Complex at Brookhaven National Laboratory, Upton, New York This Environmental Assessment addresses the proposed action by the U.S. Department of Energy to upgrade the facilities of the National Synchrotron Light Source Complex, namely the National Synchrotron Light Source (NSLS), the Accelerator Test Facility and the Source Development Laboratory. The environmental effects of a No-Action Alternative as well as a Proposed Action are evaluated in the Environmental Assessment. The “NSLS Environmental Assessment Fact Sheet” link below leads to a one-page summary of the Environmental Assessment. The “NSLS Environmental Assessment” link below leads to the whole 41-page

16

Spallation Neutron Source (SNS) | U.S. DOE Office of Science...  

Office of Science (SC) Website

(SUF) Division SUF Home About User Facilities User Facilities Dev X-Ray Light Sources Neutron Scattering Facilities High Flux Isotope Reactor (HFIR) Lujan Neutron Scattering...

17

Measurement of Thermal Neutron Flux in Photo-Neutron Source  

Science Journals Connector (OSTI)

The Photo-Neutron Source (PNS) project is a study ... design, simulation and construction an accelerator based neutron source for Boron Neutron Capture Therapy (BNCT). The system uses ... medical linear accelerat...

A. Taheri; A. Torkamani; A. Pazirandeh

2013-01-01T23:59:59.000Z

18

Spallation Neutron Source The Spallation Neutron Source (SNS)  

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

F/gim F/gim Spallation Neutron Source The Spallation Neutron Source (SNS) gives researchers more detailed informa- tion on the structure and dynamics of physical and biological materials than ever before possible. This accelerator- based facility provides the most intense pulsed neutron beams in the world. Scien- tists are able to count scattered neutrons, measure their energies and the angles at which they scatter, and map their final positions. SNS enables measurements of greater sensitivity, higher speed, higher resolution, and in more complex sample environments than have been possible at existing neutron facilities. Future Growth SNS was designed from the outset to accommodate a second target station, effectively doubling the capacity of the

19

Advanced Light Source (ALS) | U.S. DOE Office of Science (SC...  

Office of Science (SC) Website

Syncrotron Light Source (NSLS-II) Stanford Synchrotron Radiation Light Source (SSRL) Neutron Scattering Facilities Nanoscale Science Research Centers (NSRCs) Projects...

20

National Syncrotron Light Source (NSLS-II) | U.S. DOE Office...  

Office of Science (SC) Website

Syncrotron Light Source (NSLS-II) Stanford Synchrotron Radiation Light Source (SSRL) Neutron Scattering Facilities Nanoscale Science Research Centers (NSRCs) Projects...

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


21

Linac Coherent Light Source (LCLS) | U.S. DOE Office of Science...  

Office of Science (SC) Website

Syncrotron Light Source (NSLS-II) Stanford Synchrotron Radiation Light Source (SSRL) Neutron Scattering Facilities Nanoscale Science Research Centers (NSRCs) Projects...

22

X-Ray Light Sources | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Syncrotron Light Source (NSLS-II) Stanford Synchrotron Radiation Light Source (SSRL) Neutron Scattering Facilities Nanoscale Science Research Centers (NSRCs) Projects...

23

Spallation Neutron Sources Around the World  

E-Print Network [OSTI]

Spallation Neutron Sources Around the World Bernie Riemer Thanks to others for the many shamelessly Laboratory #12;2 Managed by UT-Battelle for the U.S. Department of Energy Spallation Neutron Source Facilities Spallation Neutron Source Facilities Serve Neutron Science Programs · Neutron beams to suites

McDonald, Kirk

24

National Synchrotron Light Source  

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

Report 2001 Report 2001 National Synchrotron Light Source For the period October 1, 2000 through September 30, 2001 Introduction Science Highlights Year in Review Operations Publications Abstracts Nancye Wright & Lydia Rogers The National Synchrotron Light Source Department is supported by the Office of Basic Energy Sciences United States Department of Energy Washington, D.C. Brookhaven National Laboratory Brookhaven Science Associates, Inc. Upton, New York 11973 Under Contract No. DE-AC02-98CH10886 Mary Anne Corwin Steven N. Ehrlich & Lisa M. Miller Managing Editor Science Editors Production Assistants Cover images (clockwise from top left) 1. from Science Highlight by K.R. Rajashankar, M.R. Chance, S.K. Burley, J. Jiang, S.C. Almo, A. Bresnick, T. Dodatko, R. Huang, G. He,

25

National Synchrotron Light Source  

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

All Documents listed below are part of the Photon Sciences Directorate and All Documents listed below are part of the Photon Sciences Directorate and will be updated as needed. Photon Sciences ESH Standard Operating Procedures (SOPs) SOP No. Standard Operating Procedure for: LS-ES-0002 Procedure for Acid Etching of Silicon and Germanium Crystals LS-ESH-0004 NSLS Operations Group Chemical Spill and Gas Release Response LS-ESH-0010 VUV Injection Shutter LOTO LS-ESH-0012 LINAC LOTO LS-ESH-0013 Controlled Access to the VUV Ring LS-ESH-0014 Radiation Safety Interlocks at the National Synchrotron Light Source LS-ESH-0019 Beam Line Configuration Control Checklist Requirements LS-ESH-0020 Biosafety Requirements at the NSLS LS-ESH-0021 Biosafety Level 2 work at the NSLS/ A Technical Basis LS-ESH-0022 Beam Line Configuration Control Checklist Requirements

26

SciTech Connect: Nuclear Physics: The Ultracold Neutron Source  

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 Nuclear Physics: The Ultracold Neutron Source...

27

Light Sources Directorate Strategic Plan  

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

Light Sources Directorate Light Sources Directorate Strategic Plan December 2009 Light Sources Directorate Strategic Plan December 2009 ii | Vision and Mission Light Sources Directorate Strategic Plan The VISION of the Light Sources Directorate is: to be a provider of choice for world-class photon science and facilities that deliver outstanding scientific productivity and impact, and to be recognized as a leader in developing innovative techniques and ap- plications of photon science Our MISSION is defined by the set of activities that are required to realize this vision: to advance scientific knowledge and to solve critical problems through the design, construction, operation, and use of premier photon science facilities | Table of Contents Light Sources Directorate Strategic Plan

28

Advanced Light Source  

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

Next >> Next >> Visitors Access to the ALS Gate Access guest-house Guest House lab-shuttles Lab Shuttles maps-and-directions Maps and Directions Parking Safety Safety for Users safety-for-staff Safety for Staff In Case of Emergency Resources Acronyms Multimedia Employment staff-intranet Staff Intranet Site Map Contact Digg: ALSBerkeleyLab Facebook Page: 208064938929 Flickr: advancedlightsource Twitter: ALSBerkeleyLab YouTube: AdvancedLightSource January 2014 Sun Mon Tue Wed Thu Fri Sat 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Recent Science Highlights Minding the Gap Makes for More Efficient Solar Cells Using novel materials to develop thin, flexible, and more efficient photovoltaic cells is one of the hottest topics in current materials research. A class of transition metals undergo a dramatic change that makes them ideal for solar energy applications.

29

Neutron Scattering Instrumentation for Biology at Spallation Neutron Sources  

Science Journals Connector (OSTI)

Conventional wisdom holds that since biological entities are large, they must be studied with cold neutrons, a domain in which reactor sources of neutrons are often supposed to be pre-eminent. ... fact, the curre...

Roger Pynn

1996-01-01T23:59:59.000Z

30

Presentation: Synchrotron Radiation Light Sources  

Broader source: Energy.gov [DOE]

A briefing to the Secretary's Energy Advisory Board on Synchrotron Radiation Light Sources delivered by Patricia Dehmer, U.S. Department of Energy

31

Linac Coherent Light Source Overview  

ScienceCinema (OSTI)

Take an animated tour of the Linac Coherent Light Source (LCLS). Follow the laser pulse from the injector gun all the way through to the Far Experimental Hall.

None

2013-05-29T23:59:59.000Z

32

Neutron sources and transmutation of nuclear waste  

Science Journals Connector (OSTI)

Intense neutron sources with different energy spectra are of interest for a variety of applications. In my presentation, after briefly touching on the situation of radioactive waste in Italy, I will try to give a broad picture of Italian existing or proposed neutron sources based on accelerators, ranging from thermal to fast neutrons. I will also describe a specific project for a low-power ADS, aimed at studying neutron spectra as well as at demonstrating incineration and transmutation of nuclear waste.

M. Ripani

2013-01-01T23:59:59.000Z

33

LANSCE | International Collaboration on Advanced Neutron Sources...  

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

For Admins nav background ICANS Related Sites: IPNS ICANS Proceedings International Collaboration on Advanced Neutron Sources dotline About ICANS meetings ICANS originated in...

34

Next Generation Light Source Workshops  

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

Next Generation Light Source Workshops A series of workshops will be held in late August with the goal of refining the scientific drivers for the facility and translating the...

35

Fourth Generation Light Source Workshop  

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

The Workshop on Scientific Opportunities for Fourth Generation Light The Workshop on Scientific Opportunities for Fourth Generation Light Sources October 27 to 29, 1997 at the Advanced Photon Source at Argonne National Laboratory. This workshop is being co-hosted by APS, NSLS, SSRL and TJNAF. FGLSlogo This workshop will explore the phenomenology of interactions with ultra-high-power, -brilliance, and -coherence light sources in the DUV, soft x-ray, and x-ray regimes, as well as the scientific opportunities they provide. The workshop will begin with tutorials on the generation and properties of these sources and identify issues in their use in experimentation. Also included will be an overview of current efforts to develop these sources and a review of the scientific opportunities defined by previous research and workshops. These background talks will be followed

36

Study of neutron spectra emitted by moderated 241AmBe source for various moderating materials byusing simulation technique  

Science Journals Connector (OSTI)

......light water, heavy water, graphite, 56Fe...sources of neutrons, reactors, particle accelerators...compared with nuclear reactors and neutron generators...polyethylene, light water and heavy water have been...in FLAIR (FLUKA Advanced Interface) on a......

N. Sujatha Kumari; V. Sathian; S. S. Ghodke; Yashoda Singh; A. K. Mahant; S. Ganesan

2012-06-01T23:59:59.000Z

37

Slow neutron leakage spectra from spallation neutron sources  

SciTech Connect (OSTI)

An efficient technique is described for Monte Carlo simulation of neutron beam spectra from target-moderator-reflector assemblies typical of pulsed spallation neutron sources. The technique involves the scoring of the transport-theoretical probability that a neutron will emerge from the moderator surface in the direction of interest, at each collision. An angle-biasing probability is also introduced which further enhances efficiency in simple problems. These modifications were introduced into the VIM low energy neutron transport code, representing the spatial and energy distributions of the source neutrons approximately as those of evaporation neutrons generated through the spallation process by protons of various energies. The intensity of slow neutrons leaking from various reflected moderators was studied for various neutron source arrangements. These include computations relating to early measurements on a mockup-assembly, a brief survey of moderator materials and sizes, and a survey of the effects of varying source and moderator configurations with a practical, liquid metal cooled uranium source Wing and slab, i.e., tangential and radial moderator arrangements, and Be vs CH/sub 2/ reflectors are compared. Results are also presented for several complicated geometries which more closely represent realistic arrangements for a practical source, and for a subcritical fission multiplier such as might be driven by an electron linac. An adaptation of the code was developed to enable time dependent calculations, and investigated the effects of the reflector, decoupling and void liner materials on the pulse shape.

Das, S.G.; Carpenter, J.M.; Prael, R.E.

1980-02-01T23:59:59.000Z

38

Spallation Neutron Source reaches megawatt power  

ScienceCinema (OSTI)

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.

Dr. William F. Brinkman

2010-01-08T23:59:59.000Z

39

International workshop on cold neutron sources  

SciTech Connect (OSTI)

The first meeting devoted to cold neutron sources was held at the Los Alamos National Laboratory on March 5--8, 1990. Cosponsored by Los Alamos and Oak Ridge National Laboratories, the meeting was organized as an International Workshop on Cold Neutron Sources and brought together experts in the field of cold-neutron-source design for reactors and spallation sources. Eighty-four people from seven countries attended. Because the meeting was the first of its kind in over forty years, much time was spent acquainting participants with past and planned activities at reactor and spallation facilities worldwide. As a result, the meeting had more of a conference flavor than one of a workshop. The general topics covered at the workshop included: Criteria for cold source design; neutronic predictions and performance; energy deposition and removal; engineering design, fabrication, and operation; material properties; radiation damage; instrumentation; safety; existing cold sources; and future cold sources.

Russell, G.J.; West, C.D. (comps.) (Los Alamos National Lab., NM (United States)) [comps.; Los Alamos National Lab., NM (United States)

1991-08-01T23:59:59.000Z

40

Cyclotron-based neutron source for BNCT  

SciTech Connect (OSTI)

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

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

2013-04-19T23:59:59.000Z

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


41

LightSource Renewables | Open Energy Information  

Open Energy Info (EERE)

LightSource Renewables Jump to: navigation, search Name: LightSource Renewables Place: San Diego, California Zip: 92121 Sector: Wind energy Product: Wind project developer...

42

Energy Sources and Light Curves of Macronovae  

E-Print Network [OSTI]

A macronova (kilonova) was discovered with short gamma-ray burst, GRB 130603B, which is widely believed to be powered by the radioactivity of $r$-process elements synthesized in the ejecta of a neutron star binary merger. As an alternative, we propose that macronovae are energized by the central engine, i.e., a black hole or neutron star, and the injected energy is emitted after the adiabatic expansion of ejecta. This engine model is motivated by extended emission of short GRBs. In order to compare the theoretical models with observations, we analytically formulate the light curves of macronovae. The engine model allows a wider parameter range, especially smaller ejecta mass, and better fit to observations than the $r$-process model. Future observations of electromagnetic counterparts of gravitational waves should distinguish energy sources and constrain the activity of central engine and $r$-process nucleosynthesis.

Kisaka, Shota; Takami, Hajime

2014-01-01T23:59:59.000Z

43

Advanced Neutron Source (ANS) Project progress report  

SciTech Connect (OSTI)

This report discusses the following topics on the advanced neutron source: quality assurance (QA) program; reactor core development; fuel element specification; corrosion loop tests and analyses; thermal-hydraulic loop tests; reactor control concepts; critical and subcritical experiments; material data, structural tests, and analysis; cold source development; beam tube, guide, and instrument development; hot source development; neutron transport and shielding; I C research and development; facility concepts; design; and safety.

McBee, M.R.; Chance, C.M. (eds.) (Oak Ridge National Lab., TN (USA)); Selby, D.L.; Harrington, R.M.; Peretz, F.J. (Oak Ridge National Lab., TN (USA))

1990-04-01T23:59:59.000Z

44

Observation of Neutron Skyshine from an Accelerator Based Neutron Source  

SciTech Connect (OSTI)

A key feature of neutron based interrogation systems is the need for adequate provision of shielding around the facility. Accelerator facilities adapted for fast neutron generation are not necessarily suitably equipped to ensure complete containment of the vast quantity of neutrons generated, typically >10{sup 11} n{center_dot}s{sup -1}. Simulating the neutron leakage from a facility is not a simple exercise since the energy and directional distribution can only be approximated. Although adequate horizontal, planar shielding provision is made for a neutron generator facility, it is sometimes the case that vertical shielding is minimized, due to structural and economic constraints. It is further justified by assuming the atmosphere above a facility functions as an adequate radiation shield. It has become apparent that multiple neutron scattering within the atmosphere can result in a measurable dose of neutrons reaching ground level some distance from a facility, an effect commonly known as skyshine. This paper describes a neutron detection system developed to monitor neutrons detected several hundred metres from a neutron source due to the effect of skyshine.

Franklyn, C. B. [Radiation Science Department, Necsa, PO Box 582, Pretoria 0001 (South Africa)

2011-12-13T23:59:59.000Z

45

National Synchrotron Light Source annual report 1991  

SciTech Connect (OSTI)

This report contains abstracts from research conducted at the national synchrotron light source. (LSP)

Hulbert, S.L.; Lazarz, N.N. (eds.)

1992-04-01T23:59:59.000Z

46

Cryogenic hydrogen circulation system of neutron source  

SciTech Connect (OSTI)

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

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

2014-01-29T23:59:59.000Z

47

An Accelerator Neutron Source for BNCT  

SciTech Connect (OSTI)

The overall goal of this project was to develop an accelerator-based neutron source (ABNS) for Boron Neutron Capture Therapy (BNCT). Specifically, our goals were to design, and confirm by measurement, a target assembly and a moderator assembly that would fulfill the design requirements of the ABNS. These design requirements were 1) that the neutron field quality be as good as the neutron field quality for the reactor-based neutron sources for BNCT, 2) that the patient treatment time be reasonable, 3) that the proton current required to treat patients in reasonable times be technologially achievable at reasonable cost with good reliability, and accelerator space requirements which can be met in a hospital, and finally 4) that the treatment be safe for the patients.

Blue, Thomas, E

2006-03-14T23:59:59.000Z

48

DIRECTIONAL DETECTION OF A NEUTRON SOURCE.  

SciTech Connect (OSTI)

Advantages afforded by the development of new directional neutron detectors and imagers are discussed. Thermal neutrons have mean free paths in air of about 20 meters, and can be effectively imaged using coded apertures. Fission spectrum neutrons have ranges greater than 100 meters, and carry enough energy to scatter at least twice in multilayer detectors which can yield both directional and spectral information. Such strategies allow better discrimination between a localized spontaneous fission source and the low, but fluctuating, level of background neutrons generated by cosmic rays. A coded aperture thermal neutron imager will be discussed as well as a proton-recoil double-scatter fast-neutron directional detector with time-of-flight energy discrimination.

VANIER, P.E.; FORMAN, L.

2006-10-23T23:59:59.000Z

49

Next Generation Light Source Workshops  

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

Next Generation Light Source Workshops Next Generation Light Source Workshops A series of workshops will be held in late August with the goal of refining the scientific drivers for the facility and translating the scientific needs into the technical performance requirements. Feedback from these workshops will provide important input for advancing the design of the facility. Workshops are planned in the following areas Fundamental Atomic, Molecular, Optical Physics & Combustion Dynamics Mon. Aug. 20 - Tues. Aug 21, 2012 Physical Chemistry, Catalysis, & Photosynthesis Thurs. Aug. 23 - Fri. Aug 24, 2012 Quantum Materials, Magnetism & Spin Dynamics Mon. Aug. 27 - Tues. Aug 28, 2012 Materials & Bio-imaging at the Nanoscale Thurs. Aug. 30 - Fri. Aug 31, 2012 Further information is available on the workshop website:

50

Accelerator-Driven Neutron Source for Cargo Screening  

E-Print Network [OSTI]

Accelerator-Driven Neutron Source for Cargo Screening 1 B.A.The design of an accelerator-driven neutron source isQuadrupole (RFQ) accelerator and a neutron production gas

2006-01-01T23:59:59.000Z

51

Neutron source reconstruction from pinhole imaging at National Ignition Facility  

SciTech Connect (OSTI)

The neutron imaging system at the National Ignition Facility (NIF) is an important diagnostic tool for measuring the two-dimensional size and shape of the neutrons produced in the burning deuterium-tritium plasma during the ignition stage of inertial confinement fusion (ICF) implosions at NIF. Since the neutron source is small (?100 ?m) and neutrons are deeply penetrating (>3 cm) in all materials, the apertures used to achieve the desired 10-?m resolution are 20-cm long, single-sided tapers in gold. These apertures, which have triangular cross sections, produce distortions in the image, and the extended nature of the pinhole results in a non-stationary or spatially varying point spread function across the pinhole field of view. In this work, we have used iterative Maximum Likelihood techniques to remove the non-stationary distortions introduced by the aperture to reconstruct the underlying neutron source distributions. We present the detailed algorithms used for these reconstructions, the stopping criteria used and reconstructed sources from data collected at NIF with a discussion of the neutron imaging performance in light of other diagnostics.

Volegov, P.; Danly, C. R.; Grim, G. P.; Guler, N.; Merrill, F. E.; Wilde, C. H.; Wilson, D. C. [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States); Fittinghoff, D. N.; Izumi, N.; Ma, T.; Warrick, A. L. [Livermore National Laboratory, Livermore, California 94550 (United States)] [Livermore National Laboratory, Livermore, California 94550 (United States)

2014-02-15T23:59:59.000Z

52

Science and Technology of Future Light Sources  

E-Print Network [OSTI]

and Technology of Future Light Sources Far from Equilibrium Chemical Processes in a Functional Solar Cellsolar cell (DSSC). [Source: Michael Graetzel, Swiss Federal Institute of Technology,

Bergmann, Uwe

2009-01-01T23:59:59.000Z

53

January 16, 2009: Expansion of Spallation Neutron Source | Department...  

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

the Spallation Neutron Source, expanding what is already the world's most powerful pulsed neutron scattering facility. The new station, which will cost approximately 1 billion,...

54

A neutron producing target for BINP accelerator-based neutron source B. Bayanova  

E-Print Network [OSTI]

A neutron producing target for BINP accelerator-based neutron source B. Bayanova , E. Kashaeva b l e i n f o Keywords: Target Lithium Neutron capture therapy Epithermal neutrons a b s t r a c t An innovative accelerator-based neutron source for BNCT has just started operation at the Budker Institute

Taskaev, Sergey Yur'evich

55

High Flux Isotope Reactor cold neutron source reference design concept  

SciTech Connect (OSTI)

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

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

1998-05-01T23:59:59.000Z

56

NGLS: Next Generation Light Source  

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

Lab masthead Berkeley Lab A-Z Index Phone Book Careers Search DOE logo Lab masthead Berkeley Lab A-Z Index Phone Book Careers Search DOE logo NGLS logo NGLS Science NGLS Technology Seminars Workshop/Reports Related Links Further Info NGLS Facility Combustion Photosynthesis Photosynthesis Photosynthesis Today is a golden age for light sources. Storage ring-based synchrotrons routinely provide X-ray beams exploited by thousands of scientists annually to answer fundamental questions in diverse fields including human health, energy, and electronics and information processing. MORE > NGLS Science Science section chart NGLS CD-0 Proposal NGLS Technology Technology section chart Seminars Science section chart Workshops Science section chart Last updated 06/21/2013 Top A U.S. Department of Energy National Laboratory Operated by the University

57

Secondary electron ion source neutron generator  

DOE Patents [OSTI]

A neutron generator employing an electron emitter, an ion source bombarded by the electrons from the electron emitter, a plasma containment zone, and a target situated between the plasma containment zone and the electron emitter. The target contains occluded deuterium, tritium, or a mixture thereof

Brainard, John P. (Albuquerque, NM); McCollister, Daryl R. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

58

Secondary electron ion source neutron generator  

DOE Patents [OSTI]

A neutron generator employing an electron emitter, an ion source bombarded by the electrons from the electron emitter, a plasma containment zone, and a target situated between the plasma containment zone and the electron emitter is disclosed. The target contains occluded deuterium, tritium, or a mixture thereof. 4 figs.

Brainard, J.P.; McCollister, D.R.

1998-04-28T23:59:59.000Z

59

Advanced Neutron Source (ANS) Project progress report FY 1992  

SciTech Connect (OSTI)

This report discusses project management, research and development, design, and safety at the Advanced Neutron Source facility.

Campbell, J.H. (ed.); Selby, D.L.; Harrington.

1993-01-01T23:59:59.000Z

60

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

SciTech Connect (OSTI)

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

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

2009-02-17T23:59:59.000Z

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


61

First neutron generation in the BINP accelerator based neutron source B. Bayanova  

E-Print Network [OSTI]

First neutron generation in the BINP accelerator based neutron source B. Bayanova , A. Burdakova c l e i n f o Keywords: Epithermal neutrons Lithium target Neutron capture therapy Tandem accelerator a b s t r a c t Pilot innovative facility for neutron capture therapy was built at Budker

Taskaev, Sergey Yur'evich

62

neutron density. The neutron density (nn) of the source was modeled by solving the simul-  

E-Print Network [OSTI]

neutron density. The neutron density (nn) of the source was modeled by solving the simul- taneousT is the thermal neutron velocity, l is the decay constant, Ns is the s-process abun- dance, bs� is the maxwellian-averaged neutron capture cross-section, and t0 is the average neutron exposure (21). The branching decay of 186Re

West, Stuart

63

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

SciTech Connect (OSTI)

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

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

2008-08-08T23:59:59.000Z

64

Photon Statistics of Semiconductor Light Sources.  

E-Print Network [OSTI]

??In recent years, semiconductor light sources have become more and more interesting in terms of applications due to their high efficiency and low cost. Advanced (more)

Amann, Marc

2010-01-01T23:59:59.000Z

65

Building the World's Most Advanced Light Source  

SciTech Connect (OSTI)

View this time-lapse video showing construction of the National Synchrotron Light Source II at Brookhaven National Laboratory. Construction is shown from 2009-2012.

None

2012-08-03T23:59:59.000Z

66

Advanced Neutron Source: Plant Design Requirements  

SciTech Connect (OSTI)

The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

Not Available

1990-07-01T23:59:59.000Z

67

Project of Rotating Carbon High-Power Neutron Target. Research of Graphite Properties for Production of High Intensity Neutron Source  

E-Print Network [OSTI]

Project of Rotating Carbon High-Power Neutron Target. Research of Graphite Properties for Production of High Intensity Neutron Source

Gubin, K V; Bak, P A; Kot, N K; Logatchev, P V

2001-01-01T23:59:59.000Z

68

SLAC Linac Coherent Light Source  

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

for the U.S. Department of Energy by Stanford University. As the world's most powerful X-ray laser, the LCLS creates unique light that can see details down to the size of atoms...

69

EIS-0247: Construction and Operation of the Spallation Neutron Source |  

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

247: Construction and Operation of the Spallation Neutron 247: Construction and Operation of the Spallation Neutron Source EIS-0247: Construction and Operation of the Spallation Neutron Source SUMMARY The United States needs a high-flux, short- pulsed neutron source to provide its scientific and industrial research communities with a much more intense source of pulsed neutrons for neutron scattering research than is currently available. This source would assure the availability of a state-of-the-art neutron research facility in the United States in the decades ahead. This facility would be used to conduct research in areas such as materials science, condensed matter physics, the molecular structure of biological materials, properties of polymers and complex fluids, and magnetism. In addition to creating new scientific and

70

Di-neutron correlation in light neutron-rich nuclei  

E-Print Network [OSTI]

Using a three-body model with density-dependent contact interaction, we discuss the root mean square distance between the two valence neutrons in $^{11}$Li nuclues as a function of the center of mass of the neutrons relative to the core nucleus $^9$Li. We show that the mean distance takes a pronounced minimum around the surface of the nucleus, indicating a strong surface di-neutron correlation. We demonstrate that the pairing correlation plays an essential role in this behavior. We also discuss the di-neutron structure in the $^8$He nucleus.

K. Hagino; H. Sagawa; P. Schuck

2008-12-03T23:59:59.000Z

71

NEUTRON PRODUCTION BY NEUTRAL BEAM SOURCES  

E-Print Network [OSTI]

HORSE CodeA Hultigroup Neutron and Gamma-Say Honte CarloR. Smith, "A Tantalus Fast Neutron Integrator," UCRL-17051.FiS- 9 Neutron dose during 3 months of typical TSUI

Berkner, K.H.

2010-01-01T23:59:59.000Z

72

Advanced Light Source Activity Report 2002  

SciTech Connect (OSTI)

This annual report of the Advanced Light Source details science highlights and facility improvements during the year. It also offers information on events sponsored by the facility, technical specifications, and staff and publication information.

Duque, Theresa; Greiner, Annette; Moxon, Elizabeth; Robinson, Arthur; Tamura, Lori (Editors)

2003-06-12T23:59:59.000Z

73

National Synchrotron Light Source annual report 1988  

SciTech Connect (OSTI)

This report discusses the experiment done at the National Synchrotron Light Source. Most experiments discussed involves the use of the x-ray beams to study physical properties of solid materials. (LSP)

Hulbert, S.; Lazarz, N.; Williams, G. (eds.)

1988-01-01T23:59:59.000Z

74

Novel neutron focusing mirrors for compact neutron sources  

E-Print Network [OSTI]

We demonstrated neutron beam focusing and neutron imaging using axisymmetric optics, based on pairs of confocal ellipsoid and hyperboloid mirrors. Such systems, known as Wolter mirrors, are commonly used in x-ray telescopes. ...

Gubarev, M.V.

75

UAL-BASED SIMULATION ENVIRONMENT FOR SPALLATION NEUTRON SOURCE RING.  

SciTech Connect (OSTI)

This paper outlines the major activities and applications of the Unified Accelerator Library environment for the Spallation Neutron Source (SNS) Ring.

MALITSKY,N.; SMITH,J.; WEI,J.

1999-03-29T23:59:59.000Z

76

Ashfia Huq Lead Scientist: POWGEN Spallation Neutron Source  

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

do for characterizing battery materials? Ashfia Huq Lead Scientist: POWGEN Spallation Neutron Source Oak Ridge National Laboratory 2 Presentation name Outline of talk * An...

77

Polarized neutron diffraction at a spallation source for magnetic studies  

Science Journals Connector (OSTI)

The first results from polarized neutron diffraction experiments on a time-of-flight instrument at a spallation source are reported. Higher neutron beam flux and efficient spin polarization at the neutron beamline enable in situ studies of phenomena contributing to field-induced magnetization in materials including magnetic shape memory alloys.

Pramanick, A.

2012-09-01T23:59:59.000Z

78

H- radio frequency source development at the Spallation Neutron Source  

SciTech Connect (OSTI)

The Spallation Neutron Source (SNS) now routinely operates nearly 1 MW of beam power on target with a highly persistent {approx}38 mA peak current in the linac and an availability of {approx}90%. H{sup -} beam pulses ({approx}1 ms, 60 Hz) are produced by a Cs-enhanced, multicusp ion source closely coupled with an electrostatic low energy beam transport (LEBT), which focuses the 65 kV beam into a radio frequency quadrupole accelerator. The source plasma is generated by RF excitation (2 MHz, {approx}60 kW) of a copper antenna that has been encased with a thickness of {approx}0.7 mm of porcelain enamel and immersed into the plasma chamber. The ion source and LEBT normally have a combined availability of {approx}99%. Recent increases in duty-factor and RF power have made antenna failures a leading cause of downtime. This report first identifies the physical mechanism of antenna failure from a statistical inspection of {approx}75 antennas which ran at the SNS, scanning electron microscopy studies of antenna surface, and cross sectional cuts and analysis of calorimetric heating measurements. Failure mitigation efforts are then described which include modifying the antenna geometry and our acceptance/installation criteria. Progress and status of the development of the SNS external antenna source, a long-term solution to the internal antenna problem, are then discussed. Currently, this source is capable of delivering comparable beam currents to the baseline source to the SNS and, an earlier version, has briefly demonstrated unanalyzed currents up to {approx}100 mA (1 ms, 60 Hz) on the test stand. In particular, this paper discusses plasma ignition (dc and RF plasma guns), antenna reliability, magnet overheating, and insufficient beam persistence.

Welton, Robert F [ORNL; Pennisi, Terry R [ORNL; Roseberry, Ron T [ORNL; Stockli, Martin P [ORNL

2012-01-01T23:59:59.000Z

79

SPALLATION NEUTRON SOURCE BEAM CURRENT MONITOR ELECTRONICS.  

SciTech Connect (OSTI)

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

KESSELMAN, M.

2001-06-18T23:59:59.000Z

80

Compact X-Ray Light Source Workshop | EMSL  

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

Compact X-Ray Light Source Workshop Compact X-Ray Light Source Workshop Teller R, Terminello L, Thevuthasan T, Moncton D. 2012. "Compact X-Ray Light Source Workshop Report."...

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


81

Light sources based on semiconductor current filaments  

DOE Patents [OSTI]

The present invention provides a new type of semiconductor light source that can produce a high peak power output and is not injection, e-beam, or optically pumped. The present invention is capable of producing high quality coherent or incoherent optical emission. The present invention is based on current filaments, unlike conventional semiconductor lasers that are based on p-n junctions. The present invention provides a light source formed by an electron-hole plasma inside a current filament. The electron-hole plasma can be several hundred microns in diameter and several centimeters long. A current filament can be initiated optically or with an e-beam, but can be pumped electrically across a large insulating region. A current filament can be produced in high gain photoconductive semiconductor switches. The light source provided by the present invention has a potentially large volume and therefore a potentially large energy per pulse or peak power available from a single (coherent) semiconductor laser. Like other semiconductor lasers, these light sources will emit radiation at the wavelength near the bandgap energy (for GaAs 875 nm or near infra red). Immediate potential applications of the present invention include high energy, short pulse, compact, low cost lasers and other incoherent light sources.

Zutavern, Fred J. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Buttram, Malcolm T. (Sandia Park, NM); Mar, Alan (Albuquerque, NM); Helgeson, Wesley D. (Albuquerque, NM); O'Malley, Martin W. (Edgewood, NM); Hjalmarson, Harold P. (Albuquerque, NM); Baca, Albert G. (Albuquerque, NM); Chow, Weng W. (Cedar Crest, NM); Vawter, G. Allen (Albuquerque, NM)

2003-01-01T23:59:59.000Z

82

First neutron generation in the BINP accelerator based neutron source  

Science Journals Connector (OSTI)

Pilot innovative facility for neutron capture therapy was built at Budker Institute of Nuclear Physics, Novosibirsk. This facility is based on a compact vacuum insulation tandem accelerator designed to produce proton current up to 10mA. Epithermal neutrons are proposed to be generated by 1.915MeV protons bombarding a lithium target using 7Li(p,n)7Be threshold reaction. The results of the first experiments on neutron generation are reported and discussed.

B. Bayanov; A. Burdakov; V. Chudaev; A. Ivanov; S. Konstantinov; A. Kuznetsov; A. Makarov; G. Malyshkin; K. Mekler; I. Sorokin; Yu. Sulyaev; S. Taskaev

2009-01-01T23:59:59.000Z

83

The national spallation neutron source target station: A general overview  

SciTech Connect (OSTI)

The technologies that are being utilized to design and build a state-of-the-art neutron spallation source, the National Spallation Neutron Source (NSNS), are discussed. Emphasis is given to the technology issues that present the greatest scientific challenges. The present facility configuration, ongoing analysis and the planned hardware research and development program are also described.

Gabriel, T.A.; Barnes, J.N.; Charlton, L.A. [and others

1997-06-01T23:59:59.000Z

84

The Linac Coherent Light Source is  

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

Coherent Light Source is Coherent Light Source is a revolution in x-ray science. Just as the invention of x-ray machines a century ago astonishingly revealed the inside of our bodies and began new sciences, the world's first x-ray laser will open up unprecedented opportunities. Pioneering experiments will advance our understand ing of everything from the hidden physics inside planets, to how proteins function as the engines of life, to building nanotechnology devices for the backbone of future industry and technology. The applications are legion: medicine, electronics, biology, solid-state physics, nanotechnology, energy production, industry and fields that do not yet exist. Linac Coherent Light Source New Tools Create New Science The LCLS is dramatically different from any x-ray

85

X-Ray Light Sources | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

X-Ray Light Sources X-Ray Light Sources Scientific User Facilities (SUF) Division SUF Home About User Facilities X-Ray Light Sources Neutron Scattering Facilities Nanoscale Science Research Centers Electron-Beam Microcharacterization Centers Accelerator & Detector Research & Development Principal Investigators' Meetings Scientific Highlights Construction Projects BES Home User Facilities X-Ray Light Sources Print Text Size: A A A RSS Feeds FeedbackShare Page This activity supports the operation of five DOE light sources. The unique properties of synchrotron radiation include its continuous spectrum, high flux and brightness, and in the case of the Linac Coherent Light Source, high coherence, which makes it an indispensable tool in the exploration of matter. The wavelengths of the emitted photons span a range of dimensions

86

How the Spallation Neutron Source Works | ORNL Neutron Sciences  

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

high-energy proton pulses strike a heavy-metal target, which is a container of liquid mercury. Corresponding pulses of neutrons freed by the spallation process are slowed down in...

87

NRC Construction Light Source Flicker: What We  

E-Print Network [OSTI]

frequency] (CFF) ·Health - World Health Organization (1947): · ...a state of complete physical, mental Handbook: Reference & Application (9th Ed.), 2000, p. 3-20 #12;NRC Construction Flicker Effects 1;NRC Construction Flicker Problem 2 ·Does it matter what light source produces the flicker

California at Davis, University of

88

AFRD - Advanced Light Source Accelerator Physics  

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

ALS Accelerator Physics ALS Accelerator Physics Home Organization Outreach and Diversity News Highlights Safety Links Intramural FPO Accelerator Physics Group This page and the Group's own site emphasize the continuing effort to improve the performance and versatility of the accelerator-related systems of the ALS. If you want to start with a nontechnical explanation of what synchrotron light is, how scientists use it, and how the Advanced Light Source works, try About the ALS. The research performed using beams from the ALS is a vast topic that spans many scientific disciplines; a good overview with in-depth links is available at the ALS Science Briefs page. The ALS is a “” synchrotron light source based on a low-emittance electron storage ring with a nominal energy of 1.9 GeV. Since the machine

89

A Dipole Assisted IEC Neutron Source  

SciTech Connect (OSTI)

A potential opportunity to enhance Inertial Electrostatic Confinement (IEC) fusion exists by augmenting it with a magnetic dipole configuration. The theory is that the dipole fields will enhance the plasma density in the center region of the IEC and the combined IEC and dipole confinement properties will reduce plasma losses. To demonstrate that a hybrid Dipole-IEC configuration can provide an improved neutron source vs. a stand alone IEC, a first model Dipole-IEC experiment was benchmarked against a reference IEC. A triple Langmuir probe was used to find the electron temperature and density. It was found that the magnetic field increases the electron density by a factor of 16, the electron temperature decreases in the presence of a magnetic field, the discharge voltage decreases in the presence of a magnetic field, the potential of the dipole strongly influences the densities obtained in the center. The experimental set-up and plasma diagnostics are discussed in detail, as well as the results, and the developmental issues.

Prajakti Joshi Shrestha

2005-11-28T23:59:59.000Z

90

E-Print Network 3.0 - accelerator neutron source Sample Search...  

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

driven by a powerful particle accelerator. This intense neutron source... . In subcritical systems driven by an intense external source of neutrons - in ADS. An external...

91

BINP accelerator based epithermal neutron source V. Aleynik a  

E-Print Network [OSTI]

: Boron neutron capture therapy Epithermal neutron source Accelerator a b s t r a c t Innovative facility in order to prevent the propagation of 7 Be radioactive isotope, (ii) the controlled eva- poration, which is the most power- ful and determines the further beam transport. To exclude the effect of non

Taskaev, Sergey Yur'evich

92

Backscatter absorption gas imaging systems and light sources therefore  

DOE Patents [OSTI]

The location of gases that are not visible to the unaided human eye can be determined using tuned light sources that spectroscopically probe the gases and cameras that can provide images corresponding to the absorption of the gases. The present invention is a light source for a backscatter absorption gas imaging (BAGI) system, and a light source incorporating the light source, that can be used to remotely detect and produce images of "invisible" gases. The inventive light source has a light producing element, an optical amplifier, and an optical parametric oscillator to generate wavelength tunable light in the IR. By using a multi-mode light source and an amplifier that operates using 915 nm pump sources, the power consumption of the light source is reduced to a level that can be operated by batteries for long periods of time. In addition, the light source is tunable over the absorption bands of many hydrocarbons, making it useful for detecting hazardous gases.

Kulp, Thomas Jan (Livermore, CA); Kliner, Dahv A. V. (San Ramon, CA); Sommers, Ricky (Oakley, CA); Goers, Uta-Barbara (Campbell, NY); Armstrong, Karla M. (Livermore, CA)

2006-12-19T23:59:59.000Z

93

The Argonne ACWL, a potential accelerator-based neutron source for BNCT  

Science Journals Connector (OSTI)

THE CWDD (Continuous Wave Deuterium Demonstrator) accelerator was designed to accelerate 80 mA cw of D? to 7.5 MeV. Most of the hardware for the first 2 MeV was installed at Argonne and major subsystems had been commissioned when program funding from the Ballistic Missile Defense Organization ended in October 1993. Renamed the Argonne Continuous Wave Linac (ACWL), we are proposing to complete it to accelerate either deuterons to 2 MeV or protons to 3 3.5 MeV. Equipped with a beryllium or other light-element target, it would make a potent source of neutrons (on the order of 1013 n/s) for BNCT and/or neutron radiography. Project status and proposals for turning ACWL into a neutron source are reviewed, including the results of a computational study that was carried out to design a target/moderator to produce an epithermal neutron beam for BNCT.

G.E. McMichael; T.J. Yule; X.-L. Zhou

1995-01-01T23:59:59.000Z

94

Compact, energy EFFICIENT neutron source: enabling technology for various applications  

SciTech Connect (OSTI)

A novel neutron source comprising of a deuterium beam (energy of about 100 KeV) injected into a tube filled with tritium gas and/or tritium plasma that generates D-T fusion reactions, whose products are 14.06 MeV neutrons and 3.52 MeV alpha particles, is described. At the opposite end of the tube, the energy of deuterium ions that did not interact is recovered. Beryllium walls of proper thickness can be utilized to absorb 14 MeV neutrons and release 2-3 low energy neutrons. Each ion source and tube forms a module. Larger systems can be formed from multiple units. Unlike currently proposed methods, where accelerator-based neutron sources are very expensive, large, and require large amounts of power for operation, this neutron source is compact, inexpensive, easy to test and to scale up. Among possible applications for this neutron source concept are sub-critical nuclear breeder reactors and transmutation of radioactive waste.

Hershcovitch, A.; Roser, T.

2009-12-01T23:59:59.000Z

95

Neutron sources for investigations on extracted beams in Russia  

SciTech Connect (OSTI)

An overview is presented of the current status and prospects for the development of neutron sources intended for investigations on extracted beams in Russia. The participation of Russia in international scientific organizations is demonstrated.

Aksenov, V. L. [Russian Research Centre 'Kurchatov Institute' (Russian Federation)], E-mail: Aksenov@kiae.ru

2007-05-15T23:59:59.000Z

96

Linac Coherent Light SourCe  

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

Linac Linac Coherent Light SourCe after the Stanford Linear Accelerator Center (now the SLAC National Accelerator Laboratory) developed its two- mile-long linear accelerator (linac), it received approval from the Department of Energy to construct the Linac Coherent Light Source (LCLS), the first free electron laser (FEL) facility that would be able to produce x-rays short and bright enough that individual molecules could be imaged in their natural states. 40 years Genesis of the idea In 1992, Dr. Claudio Pellegrini, a professor at UCLA, first developed a proposal for a facility that would eventually become LCLS. The idea generated interest within the scientific community, and a design study report conducted by SLAC in the late 1990s led to the first

97

Rf capacitively-coupled electrodeless light source  

DOE Patents [OSTI]

An rf capacitively-coupled electrodeless light source is provided. The light source comprises a hollow, elongated chamber and at least one center conductor disposed within the hollow, elongated chamber. A portion of each center conductor extends beyond the hollow, elongated chamber. At least one gas capable of forming an electronically excited molecular state is contained within each center conductor. An electrical coupler is positioned concentric to the hollow, elongated chamber and the electrical coupler surrounds the portion of each center conductor that extends beyond the hollow, elongated chamber. A rf-power supply is positioned in an operable relationship to the electrical coupler and an impedance matching network is positioned in an operable relationship to the rf power supply and the electrical coupler.

Manos, Dennis M. (Williamsburg, VA); Diggs, Jessie (Norfolk, VA); Ametepe, Joseph D. (Roanoke, VA); Fugitt, Jock A. (Livingston, TX)

2000-01-01T23:59:59.000Z

98

The upgraded scheme of Hefei Light Source  

SciTech Connect (OSTI)

To enhance the performance of Hefei Light Source, which was designed and constructed two decades ago, an upgrade project would be carried out in the near future. The detail upgrade scheme was described in this paper. Firstly, the magnet lattice of storage ring should be reconstructed with 4 DBA cells, whose advantages are lower beam emittance and more straight section available for insertion devices. Secondly, the beam diagnostics, main power supply, transverse and longitudinal multi-bunch feedback, beam control and manipulation system would be upgrade to improve the beam orbit stability. Finally, the injection system of storage ring and injector, which is composed of electron linac and beam transfer line, would be updated in order to assure smooth beam accumulation process under new low emittance lattice. With above improvement, it is hopeful to increase the brilliance of Hefei Light Source by two orders approximately. After three-year upgrade project, the performance of HLS would meet the demands of advanced SR users.

Li Weimin; Xu Hongliang; Wang Lin; Feng Guangyao; Zhang Shancai; Hao Hao [National Synchrotron Radiation Laboratory of University of Science and Technology of China, Anhui (China)

2010-06-23T23:59:59.000Z

99

Design and Demonstration of a Quasi-monoenergetic Neutron Source  

SciTech Connect (OSTI)

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

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

2014-03-05T23:59:59.000Z

100

Design and demonstration of a quasi-monoenergetic neutron source  

E-Print Network [OSTI]

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

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

2014-05-13T23:59:59.000Z

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


101

Fundamental Neutron Physics Beamline at the Spallation Neutron Source at ORNL  

E-Print Network [OSTI]

We describe the Fundamental Neutron Physics Beamline (FnPB) facility located at the Spallation Neutron Source at Oak Ridge National Laboratory. The FnPB was designed for the conduct of experiments that investigate scientific issues in nuclear physics, particle physics, astrophysics and cosmology using a pulsed slow neutron beam. We present a detailed description of the design philosophy, beamline components, and measured fluxes of the polychromatic and monochromatic beams.

N. Fomin; G. L. Greene; R. Allen; V. Cianciolo; C. Crawford; T. Ito; P. R. Huffman; E. B. Iverson; R. Mahurin; W. M. Snow

2014-08-04T23:59:59.000Z

102

Instrument and Source Design Division | ORNL Neutron Sciences  

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

Ron Crone, RRD Director Ron Crone, RRD Director ISDD Director Ron Crone. Instrument and Source Design Division The Instrument and Source Design Division (ISDD) supports the engineering and development of scientific instruments at the High Flux Isotope Reactor and the Spallation Neutron Source. ISDD continuously develops facilities and capabilities associated with neutron science through research and development. Organization Chart A PDF version of the ISDD Organization Chart is available. Key Division Contacts Director Ron Crone Administrative Assistant Wendy Brooks HFIR Instrument Engineering Doug Selby SNS Instrument Engineering David Vandergriff Instrumentation Projects and Development Ken Herwig Project Management/Operations and Analysis Barbara Thibadeau Source Development and Engineering Analysis Phil Ferguson

103

The JLab high power ERL light source  

SciTech Connect (OSTI)

A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz {approx} half cycle pulse whose average brightness is > 5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted[1]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [2]: up to 10 kW of average power in the IR from 1 to 14 microns in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 microseconds long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the system and discuss some of the discoveries we have made concerning the physics performance, design optimization, and operational limitations of such a first generation high power ERL light source.

G.R. Neil; C. Behre; S.V. Benson; M. Bevins; G. Biallas; J. Boyce; J. Coleman; L.A. Dillon-Townes; D. Douglas; H.F. Dylla; R. Evans; A. Grippo; D. Gruber; J. Gubeli; D. Hardy; C. Hernandez-Garcia; K. Jordan; M.J. Kelley; L. Merminga; J. Mammosser; W. Moore; N. Nishimori; E. Pozdeyev; J. Preble; R. Rimmer; Michelle D. Shinn; T. Siggins; C. Tennant; R. Walker; G.P. Williams and S. Zhang

2005-03-19T23:59:59.000Z

104

SLAC Linac Coherent Light Source User Site  

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

Welcome to the LCLS User Resources Site Welcome to the LCLS User Resources Site User Portal | Agreements | Data Collection & Analysis | Logistics | Policies | Proposals | Safety | Schedules | Shipping The Linac Coherent Light Source (LCLS) encourages scientists from diverse fields to submit proposals for experiments that utilize the LCLS's unique capabilities. Interested scientists are encouraged to learn more about the latest developments by contacting LCLS staff scientists and by reviewing the instrument descriptions. Step-By-Step Instructions to Working at LCLS Review LCLS Policies Review Machine FAQ & Parameters Register and Submit Proposals Confirm User Agreement Reserve Accommodations Complete Safety Training Request Computer Account Establish User Account Ship Samples/Equipment Review Check-in Procedures

105

Optimizing Moderator Dimensions for Neutron Scattering at the Spallation Neutron Source  

SciTech Connect (OSTI)

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

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

2013-01-01T23:59:59.000Z

106

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

SciTech Connect (OSTI)

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

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

2010-04-22T23:59:59.000Z

107

Core Vessel Insert Handling Robot for the Spallation Neutron Source  

SciTech Connect (OSTI)

The Spallation Neutron Source provides the world's most intense pulsed neutron beams for scientific research and industrial development. Its eighteen neutron beam lines will eventually support up to twenty-four simultaneous experiments. Each beam line consists of various optical components which guide the neutrons to a particular instrument. The optical components nearest the neutron moderators are the core vessel inserts. Located approximately 9 m below the high bay floor, these inserts are bolted to the core vessel chamber and are part of the vacuum boundary. They are in a highly radioactive environment and must periodically be replaced. During initial SNS construction, four of the beam lines received Core Vessel Insert plugs rather than functional inserts. Remote replacement of the first Core Vessel Insert plug was recently completed using several pieces of custom-designed tooling, including a highly complicated Core Vessel Insert Robot. The design of this tool are discussed.

Graves, Van B [ORNL; Dayton, Michael J [ORNL

2011-01-01T23:59:59.000Z

108

Dosimetry and spectrometry at accelerator based neutron source for boron neutron capture therapy  

Science Journals Connector (OSTI)

An innovative accelerator-based neutron source for boron neutron capture therapy has started operation at the Budker Institute of Nuclear Physics, Novosibirsk. This facility is based on a compact vacuum insulation tandem accelerator designed to produce proton current up to 10mA. Epithermal neutrons are proposed to be generated by 1.915MeV protons bombarding a lithium target using 7Li(p,n)7Be threshold reaction. In the article, techniques to detect neutron and gamma-rays at the facility are described. Gamma radiation is measured with NaI and BGO gamma-spectrometers. The total yield of neutrons is determined by measuring the 477keV ?-quanta from beryllium decay. For the rough analysis of the generated neutron spectrum we used bubble detectors. As the epithermal neutrons are of interest for neutron capture therapy the NaI detector is used as activation detector. We plan to use a time-of-flight technique for neutron spectra measurement. To realize this technique a new solution of short time neutron generation is proposed.

B. Bayanov; A. Burdakov; A. Kuznetsov; A. Makarov; S. Sinitskii; Yu. Sulyaev; S. Taskaev

2010-01-01T23:59:59.000Z

109

Neutron-neutron correlation in the halo dissociation of light exotic nuclei  

Science Journals Connector (OSTI)

We present model results for the two-halo-neutron correlation functions, Cnn, for the dissociation process of light exotic nuclei modelled as two neutrons and a core. A minimum is predicted for Cnn as a function of the relative momentum of the two neutrons, pnn, due to the coherence of the neutrons in the halo and final state interaction. Studying the systems Be14, Li11, and He6 within this model, we show that the numerical asymptotic limit, Cnn?1, occurs only for pnn?400MeV/c, while such limit is reached for much lower values of pnn in an independent particle model as the one used in the analysis of recent experimental data. Our model is consistent with data once the experimental correlation function is appropriately normalized.

M. T. Yamashita; T. Frederico; Lauro Tomio

2005-07-18T23:59:59.000Z

110

Advanced Light Source: Activity report 1993  

SciTech Connect (OSTI)

The Advanced Light Source (ALS) produces the world`s brightest light in the ultraviolet and soft x-ray regions of the spectrum. The first low-energy third-generation synchrotron source in the world, the ALS provides unprecedented opportunities for research in science and technology not possible anywhere else. This year marked the beginning of operations and the start of the user research program at the ALS, which has already produced numerous high quality results. A national user facility located at Lawrence Berkeley Laboratory of the University of California, the ALS is available to researchers from academia, industry, and government laboratories. This report contains the following: (1) director`s message; (2) operations overview; (3) user program; (4) users` executive committee; (5) industrial outreach; (6) accelerator operations; (7) beamline control system; (8) insertion devices; (9) experimental systems; (10) beamline engineering; (11) first results from user beamlines; (12) beamlines for 1994--1995; (13) special events; (14) publications; (15) advisory panels; and (16) ALS staff.

Not Available

1994-11-01T23:59:59.000Z

111

The Spallation Neutron Source A Powerful Tool for Materials Research  

E-Print Network [OSTI]

The wavelengths and energies of thermal and cold neutrons are ideally matched to the length and energy scales in the materials that underpin technologies of the present and future: ranging from semiconductors to magnetic devices, composites to biomaterials and polymers. The Spallation Neutron Source (SNS) will use an accelerator to produce the most intense beams of neutrons in the world when it is complete at the end of 2005. The project is being built by a collaboration of six U.S. Department of Energy laboratories. It will serve a diverse community of users drawn from academia, industry, and government labs with interests in condensed matter physics, chemistry, engineering materials, biology, and beyond.

Mason, Thomas E; Crawford, R K; Herwig, K W; Klose, F; Ankner, J F

2000-01-01T23:59:59.000Z

112

One-neutron knockout from light neutron-rich nuclei at relativistic energies  

Science Journals Connector (OSTI)

One-neutron knockout reactions from neutron-rich nuclei, with Z=6-13 and N=8-22, were studied at the Fragment Separator (GSI) at high beam energies, around 700MeV/nucleon. Structural phenomena such as the formation of one-neutron halos in odd-mass carbon isotopes (C15,17,19) will be discussed. In addition, one-neutron knockout measurements from N22 were carried out for the first time and demonstrate clearly the change from a 0d5/2 to a 1s1/2 orbital for the valence neutron, an effect that is expected above N=14 and that was also observed in O23 and F24. The possibility of an anomalous structure of F26, due to a significant 1s1/2 neutron admixture, will also be discussed in the light of the experimental data obtained in this work. Finally, the ground-state configuration of neutron-rich neon isotopes (Ne24-28) was studied, providing new information in a region that is relatively close to the island of inversion.

C. Rodrguez-Tajes et al.

2010-08-05T23:59:59.000Z

113

Materials for cold neutron sources: Cryogenic and irradiation effects  

SciTech Connect (OSTI)

Materials for the construction of cold neutron sources must satisfy a range of demands. The cryogenic temperature and irradiation create a severe environment. Candidate materials are identified and existing cold sources are briefly surveyed to determine which materials may be used. Aluminum- and magnesium-based alloys are the preferred materials. Existing data for the effects of cryogenic temperature and near-ambient irradiation on the mechanical properties of these alloys are briefly reviewed, and the very limited information on the effects of cryogenic irradiation are outlined. Generating mechanical property data under cold source operating conditions is a daunting prospect. It is clear that the cold source material will be degraded by neutron irradiation, and so the cold source must be designed as a brittle vessel. The continued effective operation of many different cold sources at a number of reactors makes it clear that this can be accomplished. 46 refs., 8 figs., 2 tab.

Alexander, D.J.

1990-01-01T23:59:59.000Z

114

Neutron Stars in a Varying Speed of Light Theory  

E-Print Network [OSTI]

We study neutron stars in a varying speed of light (VSL) theory of gravity in which the local speed of light depends upon the value of a scalar field $\\phi$. We find that the masses and radii of the stars are strongly dependent on the strength of the coupling between $\\phi$ and the matter field and that for certain choices of coupling parameters, the maximum neutron star mass can be arbitrarily small. We also discuss the phenomenon of cosmological evolution of VSL stars (analogous to the gravitational evolution in scalar-tensor theories) and we derive a relation showing how the fractional change in the energy of a star is related to the change in the cosmological value of the scalar field.

A. W. Whinnett

2003-04-04T23:59:59.000Z

115

Can Handheld Plastic Detectors Do Both Gamma and Neutron Isotopic Identification with Directional Source Location?  

SciTech Connect (OSTI)

This paper demonstrates, through MCNPX simulations, that a compact hexagonal array of detectors can be utilized to do both gamma isotopic identification (ID) along with neutron identification while simultaneously finding the direction of the source relative to the detector array. The detector array itself is composed of seven borated polyvinyl toluene (PVT) hexagonal light pipes approximately 4 inches long and with a 1.25 inch face-to-face thickness assembled in a tight configuration. The gamma ID capability is realized through judicious windowing algorithms as is the neutron spectral unfolding. By having multiple detectors in different relative positions, directional determination of the source can be realized. By further adding multiplicity counters to the neutron counts, fission events can be measured.

Robert Hayes

2008-04-18T23:59:59.000Z

116

Stripped electron collection at the Spallation Neutron Source  

Science Journals Connector (OSTI)

One of the main sources of electrons in the Spallation Neutron Sources Accumulator Ring is the stripped electrons in the injection region. A magnetic field guides the stripped electrons to the bottom of the beam pipe, where an electron catcher with overhanging surface traps them. This paper describes the stripped electrons motion, the optimization of the catcher, and the build up of an electron cloud in this region.

L. Wang; Y. Y. Lee; G. Mahler; W. Meng; D. Raparia; J. Wei; S. Henderson

2005-09-13T23:59:59.000Z

117

E-Print Network 3.0 - accelerator-driven neutron source Sample...  

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

Summary: - so called Accelerator-Driven System (ADS). An external neutron source and subcritical operation open... about 3 times a year. An alternative, thermal neutron...

118

E-Print Network 3.0 - alternative neutron sources Sample Search...  

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

Search Sample search results for: alternative neutron sources Page: << < 1 2 3 4 5 > >> 1 Neutron Scattering Society of America Purpose and New Initiatives Summary: CONCERNS about...

119

A high-fluence fusion neutron source  

SciTech Connect (OSTI)

A conceptual design of a D-T fusion facility for continuous production of 14-MeV neutron wall loading from 5 to 10 MW/m/sup 2/ at the plasma surface is presented. In this design, D-T neutrons are produced in a linear, two-component plasma formed by neutral beam irradiation of a fully ionized warm plasma target. The beam energy, which is deposited in the center, is transferred to the warm plasma mainly by electron drag and is conducted along the target plasma column to end regions where it is absorbed in neutral gas at high pressure. The target plasma is operated in a regime where electron thermal conduction along the column is the controlling energy-loss process. The loss rate is minimized by adjusting the diameter and length of the plasma column. A substantial gradient in T/sub e/ along the column results in recombination of the plasma to gas in the end-regions before impact on the end walls. The resultant hot gas is cooled by contact with large-area heat exchangers. In this way, the large steady-state heat load from the injected neutral beams is diffused and removed at tolerable heat flux levels. The reacting plasma is essentially an extrapolation of the 2XIIB high-..beta.. plasma to higher magnetic field, ion energy, and density. 12 refs., 4 figs.

Coensgen, F.H.; Casper, T.A.; Correll, D.L.; Damm, C.C.; Futch, A.H.; Logan, B.G.; Molvik, A.W.; Bulmer, R.H.

1988-02-17T23:59:59.000Z

120

The 4th Generation Light Source at Jefferson Lab  

SciTech Connect (OSTI)

A number of "Grand Challenges" in Science have recently been identified in reports from The National Academy of Sciences, and the U.S. Dept. of Energy, Basic Energy Sciences. Many of these require a new generation of linac-based light source to study dynamical and non-linear phenomena in nanoscale samples. In this paper we present a summary of the properties of such light sources, comparing them with existing sources, and then describing in more detail a specific source at Jefferson Lab. Importantly, the JLab light source has developed some novel technology which is a critical enabler for other new light sources.

Stephen Benson; George Biallas; James Boyce; Donald Bullard; James Coleman; David Douglas; H. Dylla; Richard Evans; Pavel Evtushenko; Albert Grippo; Christopher Gould; Joseph Gubeli; David Hardy; Carlos Hernandez-Garcia; Kevin Jordan; John Klopf; Steven Moore; George Neil; Thomas Powers; Joseph Preble; Daniel Sexton; Michelle D. Shinn; Christopher Tennant; Richard Walker; Shukui Zhang; Gwyn Williams

2007-04-25T23:59:59.000Z

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


121

The new cold neutron chopper spectrometer at the Spallation Neutron Source: Design and performance  

SciTech Connect (OSTI)

The design and performance of the new cold neutron chopper spectrometer (CNCS) at the Spallation Neutron Source in Oak Ridge are described. CNCS is a direct-geometry inelastic time-of-flight spectrometer, designed essentially to cover the same energy and momentum transfer ranges as IN5 at ILL, LET at ISIS, DCS at NIST, TOFTOF at FRM-II, AMATERAS at J-PARC, PHAROS at LANSCE, and NEAT at HZB, at similar energy resolution. Measured values of key figures such as neutron flux at sample position and energy resolution are compared between measurements and ray tracing Monte Carlo simulations, and good agreement (better than 20% of absolute numbers) has been achieved. The instrument performs very well in the cold and thermal neutron energy ranges, and promises to become a workhorse for the neutron scattering community for quasielastic and inelastic scattering experiments.

Ehlers, G.; Podlesnyak, A. A.; Niedziela, J. L.; Iverson, E. B. [Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Sokol, P. E. [Department of Physics, Indiana University, Bloomington, Indiana 47405 (United States)

2011-08-15T23:59:59.000Z

122

Status of the SAGA Light Source  

SciTech Connect (OSTI)

The SAGA Light Source (SAGA-LS) is a synchrotron radiation facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring that is 75.6 m in circumference. The SAGA-LS has been stably providing synchrotron radiation to users since it first started user operation in February 2006. Along with the user operation, various machine improvements have been made over the past years, including upgrading the injector linac control system, replacing a septum magnet and constructing a beam diagnostic system. In addition to these improvements, insertion devices have been developed and installed. An APPLE-II type variable polarization undulator was installed in 2008. To address the demand from users for high-flux hard x-rays, a superconducting 4 T class wiggler is being developed. An experimental setup for generating MeV photons by laser Compton scattering is being constructed for beam monitoring and future user experiments.

Kaneyasu, T.; Takabayashi, Y.; Iwasaki, Y.; Koda, S. [SAGA Light Sources, 8-7 Yayoigaoka, Tosu, Saga 841-0005 (Japan)

2010-06-23T23:59:59.000Z

123

E-Print Network 3.0 - ambe source neutron Sample Search Results  

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

IN PHYSICS RESEARCH Section A Theory of neutron fluctuations in source-driven subcritical systems... source 1. Introduction ... Source: Pzsit, Imre - Department of Reactor...

124

Photo-Neutron Sources and the Energy of the Photo-Neutrons  

Science Journals Connector (OSTI)

In a preliminary study photo-neutrons were observed to be produced by the ?-rays from Na24, Mn56, Ga72, As76, and La140 when these artificially radioactive isotopes were placed in D2O or Be; F20, Al28, Cl38, In116, and Sb124 produced neutrons only in Be. The first group of isotopes must have ?-rays with energy higher than 2.18 Mev, and the second group must have ?-rays greater than 1.63 Mev but less than 2.18 Mev. No photo-neutrons were observed from Co60, Cu64, Ag (225 day -life), Pr142, Eu151, Dy165, Ta182, Re188, Ir (19 hours -life), and Au198 in Be; the intense ?-rays from these isotopes must have energies less than 1.63 Mev. In a second experiment the energy of the photo-neutrons from nine of these sources was determined by measuring the hydrogen scattering cross section of the emitted neutrons. Seven, of the sources seem to emit homogeneous groups of neutrons; they are: Sb+Be, Ga+D2O, La+D2O, Mn+D2O, Na+D2O, La+Be, and Na+Be with neutron energies 0.024, 0.13, 0.13, 0.22, 0.22, 0.62, and 0.83 Mev, respectively, for the particular sized sources studied. Mn+Be emits three groups of neutrons of different energies, but more than 80 percent of the neutrons seem to be in a group at 0.14 Mev. The energy of the ?-rays calculated to produce neutrons of these energies are: for Na24, 2.74 Mev; for Mn56, 1.81 and 2.7 Mev (a third ?-ray is present); for Ga72, 2.50 Mev (at least one other ?-ray is present with an energy between 2.2 and 1.63 Mev); for Sb124, 1.67 Mev; and for La140, 2.49 Mev. The total neutron cross section of carbon is also given for seven of these photo-neutron sources.

A. Wattenberg

1947-04-15T23:59:59.000Z

125

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

DOE Patents [OSTI]

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

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

1999-01-01T23:59:59.000Z

126

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

DOE Patents [OSTI]

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

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

1999-05-11T23:59:59.000Z

127

Ideas for Future Synchrotron Light Sources  

E-Print Network [OSTI]

of very-high-brightness electron sources, it is anticipatedcharacteristics for the electron source, given in u_ble 1.Table 1 Electron Source Characteristics Characteristic f

Jackson, A.

2011-01-01T23:59:59.000Z

128

Accelerator shield design of KIPT neutron source facility  

SciTech Connect (OSTI)

Argonne National Laboratory (ANL) of the United States and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the design development of a neutron source facility at KIPT utilizing an electron-accelerator-driven subcritical assembly. Electron beam power is 100 kW, using 100 MeV electrons. The facility is designed to perform basic and applied nuclear research, produce medical isotopes, and train young nuclear specialists. The biological shield of the accelerator building is designed to reduce the biological dose to less than 0.5-mrem/hr during operation. The main source of the biological dose is the photons and the neutrons generated by interactions of leaked electrons from the electron gun and accelerator sections with the surrounding concrete and accelerator materials. The Monte Carlo code MCNPX serves as the calculation tool for the shield design, due to its capability to transport electrons, photons, and neutrons coupled problems. The direct photon dose can be tallied by MCNPX calculation, starting with the leaked electrons. However, it is difficult to accurately tally the neutron dose directly from the leaked electrons. The neutron yield per electron from the interactions with the surrounding components is less than 0.01 neutron per electron. This causes difficulties for Monte Carlo analyses and consumes tremendous computation time for tallying with acceptable statistics the neutron dose outside the shield boundary. To avoid these difficulties, the SOURCE and TALLYX user subroutines of MCNPX were developed for the study. The generated neutrons are banked, together with all related parameters, for a subsequent MCNPX calculation to obtain the neutron and secondary photon doses. The weight windows variance reduction technique is utilized for both neutron and photon dose calculations. Two shielding materials, i.e., heavy concrete and ordinary concrete, were considered for the shield design. The main goal is to maintain the total dose outside the shield boundary at less than 0.5-mrem/hr. The shield configuration and parameters of the accelerator building have been determined and are presented in this paper. (authors)

Zhong, Z.; Gohar, Y. [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States)

2013-07-01T23:59:59.000Z

129

Optimizing moderator dimensions for neutron scattering at the spallation neutron source  

SciTech Connect (OSTI)

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

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

2013-12-15T23:59:59.000Z

130

Lighting Group: Sources and Ballasts: HID Lighting Systems  

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

Ballasts and Controls for HID Lighting Ballasts and Controls for HID Lighting Systems Evaluation of Electronic Ballasts and Related Controls for HID Lighting Systems Objective HID ballast The goal of this project is to evaluate the potential of electronic ballasts and related controls for HID lighting systems to improve the efficiency of current technology. The specific objectives of this project are to: Test, analyze and determine the potential of electronic ballasts for HID lighting systems in cooperation with manufacturers as an emerging energy efficient technology to reduce lighting loads in commercial, industrial and municipal applications. Identify control strategies to further improve the energy efficiency of these systems with a municipal partner. Provide appropriate recommendations for incorporating these technologies into current state codes and regulations.

131

Dense Plasma Focus Fusion Neutron Sources Progress at NSTec, September 2011  

SciTech Connect (OSTI)

A number of dense plasma focus (DPF) sources are introduced, including their operating characteristics and current activities. Neutron resonance spectroscopy is discussed and the feasibility of using DPF for neutron sources is considered.

Hagen, E. C.

2011-07-02T23:59:59.000Z

132

Science and Instrumentation for the Linac Coherent Light Source...  

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

of the proposed Linac Coherent Light Source (LCLS): subpicosecond time-structure, coherence and unprecedented high averagepeak brightness in the angstrom spectral region. The...

133

Small plasma focus as neutron pulsed source for nuclides identification  

SciTech Connect (OSTI)

In this paper, we present preliminary results on the feasibility of employing a low energy (2 kJ, 31 kV) plasma focus device as a portable source of pulsed neutron beams (2.45 MeV) generated by nuclear fusion reactions D-D, for the in situ analysis of substances by nuclear activation. This source has the relevant advantage of being pulsed at requirement, transportable, not permanently radioactive, without radioactive waste, cheap, among others. We prove the feasibility of using this source showing several spectra of the characteristic emission line for manganese, gold, lead, and silver.

Milanese, M.; Moroso, R.; Barbaglia, M. [Centro de Investigaciones en Fsica e Ingeniera del Centro de la Provincia de Buenos Aires (CONICET-UNCPBA), Pinto 399, Tandil 7000, Buenos Aires (Argentina) [Centro de Investigaciones en Fsica e Ingeniera del Centro de la Provincia de Buenos Aires (CONICET-UNCPBA), Pinto 399, Tandil 7000, Buenos Aires (Argentina); Universidad del Centro de la Provincia de Buenos Aires (CONICET-UNCPBA), Pinto 399, Tandil 7000, Buenos Aires (Argentina); Niedbalski, J. [CONICET(Consejo Nacional de Investigaciones Cientficas y Tcnicas), Rivadavia 1917, Buenos Aires (Argentina)] [CONICET(Consejo Nacional de Investigaciones Cientficas y Tcnicas), Rivadavia 1917, Buenos Aires (Argentina); Mayer, R. [CNEA (Comisin Nacional de Energa Atmica), Av. Bustillo 9500, San Carlos de Bariloche, Rio Negro (Argentina)] [CNEA (Comisin Nacional de Energa Atmica), Av. Bustillo 9500, San Carlos de Bariloche, Rio Negro (Argentina); Castillo, F. [UNAM (Universidad Nacional Autnoma de Mxico)Circuito Exterior s/n, Ciudad Universitaria, Delg. Coyoacn, P.O. Box 70-543, Mxico DF (Mexico)] [UNAM (Universidad Nacional Autnoma de Mxico)Circuito Exterior s/n, Ciudad Universitaria, Delg. Coyoacn, P.O. Box 70-543, Mxico DF (Mexico); Guichn, S. [Universidad del Centro de la Provincia de Buenos Aires (CONICET-UNCPBA), Pinto 399, Tandil 7000, Buenos Aires (Argentina)] [Universidad del Centro de la Provincia de Buenos Aires (CONICET-UNCPBA), Pinto 399, Tandil 7000, Buenos Aires (Argentina)

2013-10-15T23:59:59.000Z

134

Small plasma focus as neutron pulsed source for nuclides identification  

Science Journals Connector (OSTI)

In this paper we present preliminary results on the feasibility of employing a low energy (2 kJ 31 kV) plasma focus device as a portable source of pulsed neutron beams (2.45 MeV) generated by nuclear fusion reactions D-D for the in situ analysis of substances by nuclear activation. This source has the relevant advantage of being pulsed at requirement transportable not permanently radioactive without radioactive waste cheap among others. We prove the feasibility of using this source showing several spectra of the characteristic emission line for manganese gold lead and silver.

M. Milanese; J. Niedbalski; R. Moroso; M. Barbaglia; R. Mayer; F. Castillo; S. Guichn

2013-01-01T23:59:59.000Z

135

Radionuclide neutron sources in calibration laboratoryneutron and gamma doses and their changes in time  

Science Journals Connector (OSTI)

......oxfordjournals.org August 2007 research-article POSTER Presentations Radionuclide neutron sources in calibration...This work was partially supported by the Ministry of Science and Higher Education of Poland; grant No 2P05 D06530. REFERENCES 1 ISO......

K. Jzefowicz; N. Golnik; P. Tulik; M. Zielczynski

2007-08-01T23:59:59.000Z

136

Installing a Light Source 'Racetrack' | Department of Energy  

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

Installing a Light Source 'Racetrack' Installing a Light Source 'Racetrack' Installing a Light Source 'Racetrack' March 22, 2011 - 10:42am Addthis Brookhaven National Lab's NSLS II Construction Site | Photo Courtesy of Brookhaven National Lab Brookhaven National Lab's NSLS II Construction Site | Photo Courtesy of Brookhaven National Lab Kendra Snyder This month, workers at Brookhaven National Laboratory's National Synchrotron Light Source II (NSLS-II), the half-mile electron racetrack for one of the world's most advanced light sources, will begin filling the facility's steel and concrete shell. In 2015, NSLS-II will open its doors - and its ultra-bright beams of x-ray, infrared and ultraviolet light - to thousands of researchers around the world, enabling the detailed exploration of everything from

137

Installing a Light Source 'Racetrack' | Department of Energy  

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

Installing a Light Source 'Racetrack' Installing a Light Source 'Racetrack' Installing a Light Source 'Racetrack' March 22, 2011 - 10:42am Addthis Brookhaven National Lab's NSLS II Construction Site | Photo Courtesy of Brookhaven National Lab Brookhaven National Lab's NSLS II Construction Site | Photo Courtesy of Brookhaven National Lab Kendra Snyder This month, workers at Brookhaven National Laboratory's National Synchrotron Light Source II (NSLS-II), the half-mile electron racetrack for one of the world's most advanced light sources, will begin filling the facility's steel and concrete shell. In 2015, NSLS-II will open its doors - and its ultra-bright beams of x-ray, infrared and ultraviolet light - to thousands of researchers around the world, enabling the detailed exploration of everything from

138

A Web Site about the International Light Source Community  

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

A Web Site about the International Light Source Community A Web Site about the International Light Source Community On February 17, 2005, the international light source community, including the Advanced Photon Source at Argonne National Laboratory, launched the first website dedicated to providing the media, general public, and scientific community with the latest news and information about and from the world's accelerator-driven light sources (synchrotrons and free-electron lasers) and about the science carried out by users of these facilities. The web site - www.lightsources.org - was developed and is jointly maintained by the lightsource.org Collaboration, whose members represent the world's light source facilities in Europe, North America, and Asia. Support for the project is provided by science funding agencies of many

139

The Neutron Science TeraGrid Gateway, a TeraGrid Science Gateway to Support the Spallation Neutron Source  

E-Print Network [OSTI]

1 The Neutron Science TeraGrid Gateway, a TeraGrid Science Gateway to Support the Spallation Neutron Source John W. Cobb* , Al Geist* , James A. Kohl* , Stephen D. Miller , Peter F. Peterson] is entering its operational phase. An ETF science gateway effort is the Neutron Science TeraGrid Gateway (NSTG

Vazhkudai, Sudharshan

140

Inorganic volumetric light source excited by ultraviolet light  

DOE Patents [OSTI]

The invention relates to a composition for the volumetric generation of radiation. The composition comprises a porous substrate loaded with a component capable of emitting radiation upon interaction with an exciting radiation. Preferably, the composition is an aerogel substrate loaded with a component, e.g., a phosphor, capable of interacting with exciting radiation of a first energy, e.g., ultraviolet light, to produce radiation of a second energy, e.g., visible light.

Reed, Scott (Albuquerue, NM); Walko, Robert J. (Albuquerue, NM); Ashley, Carol S. (Albuquerue, NM); Brinker, C. Jeffrey (Albuquerue, NM)

1994-01-01T23:59:59.000Z

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


141

The Phase I MX Beamlines at Diamond Light Source  

SciTech Connect (OSTI)

Three beamlines dedicated to macromolecular crystallography, I02, I03 and I04 at Diamond Light Source are presented. These beamlines formed the life science component of Phase 1 of Diamond Light Source. The article provides details of the design and the current status of the beamlines.

Duke, E. M. H.; Evans, G.; Flaig, R.; Hall, D. R.; Latchem, M.; McAuley, K. E.; Sandy, D. J.; Sorensen, T. L-M.; Waterman, D.; Johnson, L. N. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxon. OX11 0DE (United Kingdom)

2010-06-23T23:59:59.000Z

142

Linac Coherent Light Source Overview | Department of Energy  

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

Linac Coherent Light Source Overview Linac Coherent Light Source Overview Linac Coherent Light Source Overview Addthis Description Take an animated tour of the Linac Coherent Light Source (LCLS). Follow the laser pulse from the injector gun all the way through to the Far Experimental Hall. Duration 5:50 Topic Physics Credit Energy Department Video MR. : The SLAC National Accelerator Laboratory is located in the heart of California's beautiful San Francisco Bay Area. Operated by Stanford University for the U.S. Department of Energy, SLAC has been home to the world's longest particle accelerator for nearly 50 years. In 2009 SLAC ushered in a new era in its long history of physics research with a new kind of laser called the Linac Coherent Light Source, or LCLS. The LCLS is the first laser in the world to produce hard X-rays, which can

143

The Advanced Neutron Source research and development plan  

SciTech Connect (OSTI)

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.

Selby, D.L.

1992-11-30T23:59:59.000Z

144

The Advanced Neutron Source research and development plan  

SciTech Connect (OSTI)

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.

Selby, D.L.

1992-11-30T23:59:59.000Z

145

Elemental composition in sealed plutoniumberyllium neutron sources  

Science Journals Connector (OSTI)

Abstract Five sealed plutoniumberyllium (PuBe) neutron sources from various manufacturers were disassembled. Destructive chemical analyses for recovered PuBe materials were conducted for disposition purposes. A dissolution method for PuBe alloys was developed for quantitative plutonium (Pu) and beryllium (Be) assay. Quantitation of Be and trace elements was performed using plasma based spectroscopic instruments, namely inductively coupled plasma mass spectrometry (ICP-MS) and atomic emission spectrometry (ICP-AES). Pu assay was accomplished by an electrochemical method. Variations in trace elemental contents among the five PuBe sources are discussed.

N. Xu; K. Kuhn; D. Gallimore; A. Martinez; M. Schappert; D. Montoya; E. Lujan; K. Garduno; L. Tandon

2015-01-01T23:59:59.000Z

146

Advanced Neutron Source: Plant Design Requirements. Revision 4  

SciTech Connect (OSTI)

The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

Not Available

1990-07-01T23:59:59.000Z

147

SNS/BNL Diagnostics System Group, Spallation Neutron Source, SNS  

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

SNS/BNL Diagnostics System Group SNS/BNL Diagnostics System Group Homepage The Spallation Neutron Source project is a collaboration between six national laboratories of the United states to build a Mega Watt neutrons source driven by a proton accelerator. The complex is going to be build in Oak Ridge (Tennessee) and consists of a full energy (1 Gev) linac, an accumulator ring and a mercury target with several instruments for neutron scattering. Information on the project can be found at http://www.sns.gov. At Brookhaven National Laboratory we work mainly on the accumulator ring and transfer lines diagnostics (HEBT, Ring, RTBT). Some of the systems are SNS-wide ie: the Beam Loss Monitor system and Beam Current Monitor system. In addition our group provides parts of other systems to our partner laboratories. Our group is part or the Collider Accelerator Division that is also in charge of RHIC and the AGS complex. If you are looking for information on a particular topic you can contact the persons working on it.

148

Neutron source in the MCNPX shielding calculating for electron accelerator driven facility  

SciTech Connect (OSTI)

Argonne National Laboratory (ANL) of USA and Kharkov Inst. of Physics and Technology (KIPT) of Ukraine have been collaborating on the design development of an experimental neutron source facility. It is an accelerator driven system (ADS) utilizing a subcritical assembly driven by electron accelerator. The facility will be utilized for performing basic and applied nuclear researches, producing medical isotopes, and training young nuclear specialists. Monte Carlo code MCNPX has been utilized as a design tool due to its capability to transport electrons, photons, and neutrons at high energies. However the facility shielding calculations with MCNPX need enormous computational resources and the small neutron yield per electron makes sampling difficulty for the Monte Carlo calculations. A method, based on generating and utilizing neutron source file, was proposed and tested. This method reduces significantly the required computer resources and improves the statistics of the calculated neutron dose outside the shield boundary. However the statistical errors introduced by generating the neutron source were not directly represented in the results, questioning the validity of this methodology, because an insufficiently sampled neutron source can cause error on the calculated neutron dose. This paper presents a procedure for the validation of the generated neutron source file. The impact of neutron source statistic on the neutron dose is examined by calculating the neutron dose as a function of the number of electron particles used for generating the neutron source files. When the value of the calculated neutron dose converges, it means the neutron source has scored sufficient records and statistic does not have apparent impact on the calculated neutron dose. In this way, the validity of neutron source and the shield analyses could be verified. (authors)

Zhong, Z.; Gohar, Y. [Nuclear Engineering Div., Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

2012-07-01T23:59:59.000Z

149

Photon Sciences | About the National Synchrotron Light Source  

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

Source Source NSLS One of the world's most widely used scientific research facilities, the National Synchrotron Light Source (NSLS) is host each year to 2,400 researchers from more than 400 universities, laboratories, and companies. Research conducted at the NSLS has yielded advances in biology, physics, chemistry, geophysics, medicine, and materials science. Synchrotron light is produced by electrons when they are forced to move in a curved path at nearly the speed of light. At the NSLS, beams of light in the x-ray, ultraviolet, and infrared wavelengths are produced by two synchrotrons for use in experiments. Powerful Light, Diverse Research Since the intensity of synchrotron light can be 10,000 times greater than conventional beams generated in a laboratory, scientists can use these

150

Lighting Group: Sources and Ballasts: OLED Cathodes  

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

OLED Cathodes OLED Cathodes Development of New Cathodes for OLED's Objective The objective of this project is to develop improved cathodes for use in organic light emitting diodes (OLEDs). Approach A major challenge for organic light emitting diode (OLED) technology is to improve electron injection into the organic electroluminescent layer, which limits the efficiency of the device and the luminous flux per unit area. This project aims at overcoming such barriers by developing “structured cathodes” based on functional materials (nanotubes and nanoclusters) with characteristic size smaller than the optical wavelength. The incorporation of such nanostructured cathodes in OLEDs can significantly improve device efficiency by lowering operating voltage, and increase device stability and light extraction.

151

A SEARCH FOR POINT SOURCES OF EeV NEUTRONS  

SciTech Connect (OSTI)

A thorough search of the sky exposed at the Pierre Auger Cosmic Ray Observatory reveals no statistically significant excess of events in any small solid angle that would be indicative of a flux of neutral particles from a discrete source. The search covers from -90 Degree-Sign to +15 Degree-Sign in declination using four different energy ranges above 1 EeV (10{sup 18} eV). The method used in this search is more sensitive to neutrons than to photons. The upper limit on a neutron flux is derived for a dense grid of directions for each of the four energy ranges. These results constrain scenarios for the production of ultrahigh energy cosmic rays in the Galaxy.

Abreu, P.; Andringa, S. [LIP and Instituto Superior Tecnico, Technical University of Lisbon (Portugal); Aglietta, M. [Istituto di Fisica dello Spazio Interplanetario (INAF), Universita di Torino and Sezione INFN, Torino (Italy); Ahlers, M. [University of Wisconsin, Madison, WI (United States); Ahn, E. J. [Fermilab, Batavia, IL (United States); Albuquerque, I. F. M. [Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo, SP (Brazil); Allard, D. [Laboratoire AstroParticule et Cosmologie (APC), Universite Paris 7, CNRS-IN2P3, Paris (France); Allekotte, I. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), San Carlos de Bariloche (Argentina); Allen, J. [New York University, New York, NY (United States); Allison, P. [Ohio State University, Columbus, OH (United States); Almela, A. [Facultad Regional Buenos Aires, Universidad Tecnologica Nacional, Buenos Aires (Argentina); Alvarez Castillo, J. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico); Alvarez-Muniz, J. [Universidad de Santiago de Compostela (Spain); Alves Batista, R. [IFGW, Universidade Estadual de Campinas, Campinas, SP (Brazil); Ambrosio, M.; Aramo, C. [Universita di Napoli 'Federico II' and Sezione INFN, Napoli (Italy); Aminaei, A. [IMAPP, Radboud University Nijmegen (Netherlands); Anchordoqui, L. [University of Wisconsin, Milwaukee, WI (United States); Antici'c, T. [Rudjer Boskovi'c Institute, 10000 Zagreb (Croatia); Arganda, E. [IFLP, Universidad Nacional de La Plata and CONICET, La Plata (Argentina); Collaboration: Pierre Auger Collaboration; and others

2012-12-01T23:59:59.000Z

152

Advanced Neutron Source Reactor thermal analysis of fuel plate defects  

SciTech Connect (OSTI)

The Advanced Neutron Source Reactor (ANSR) is a research reactor designed to provide the highest continuous neutron beam intensity of any reactor in the world. The present technology for determining safe operations were developed for the High Flux Isotope Reactor (HFIR). These techniques are conservative and provide confidence in the safe operation of HFIR. However, the more intense requirements of ANSR necessitate the development of more accurate, but still conservative, techniques. This report details the development of a Local Analysis Technique (LAT) that provides an appropriate approach. Application of the LAT to two ANSR core designs are presented. New theories of the thermal and nuclear behavior of the U{sub 3}Si{sub 2} fuel are utilized. The implications of lower fuel enrichment and of modifying the inspection procedures are also discussed. Development of the computer codes that enable the automate execution of the LAT is included.

Giles, G.E.

1995-08-01T23:59:59.000Z

153

Designing subwavelength-structured light sources  

E-Print Network [OSTI]

The laser has long been established as the best possible optical source for fundamental studies and applications requiring high field intensity, single mode operation, a high degree of coherence, a narrow linewidth and ...

Chua, Song Liang

2013-01-01T23:59:59.000Z

154

Lighting system combining daylight concentrators and an artificial source  

DOE Patents [OSTI]

A combined lighting system for a building interior includes a stack of luminescent solar concentrators (LSC), an optical conduit made of preferably optical fibers for transmitting daylight from the LSC stack, a collimating lens set at an angle, a fixture for receiving the daylight at one end and for distributing the daylight as illumination inside the building, an artificial light source at the other end of the fixture for directing artifical light into the fixture for distribution as illumination inside the building, an automatic dimmer/brightener for the artificial light source, and a daylight sensor positioned near to the LSC stack for controlling the automatic dimmer/brightener in response to the daylight sensed. The system also has a reflector positioned behind the artificial light source and a fan for exhausting heated air out of the fixture during summer and for forcing heated air into the fixture for passage into the building interior during winter.

Bornstein, Jonathan G. (Miami, FL); Friedman, Peter S. (Toledo, OH)

1985-01-01T23:59:59.000Z

155

Synchronization System for Next Generation Light Sources  

SciTech Connect (OSTI)

An alternative synchronization technique one that would allow explicit control of the pulse train including its repetition rate and delay is clearly desired. We propose such a scheme. Our method is based on optical interferometry and permits synchronization of the pulse trains generated by two independent mode-locked lasers. As the next generation x-ray sources will be driven by a clock signal derived from a mode-locked optical source, our technique will provide a way to synchronize x-ray probe with the optical pump pulses.

Zavriyev, Anton

2014-03-27T23:59:59.000Z

156

Large area, surface discharge pumped, vacuum ultraviolet light source  

DOE Patents [OSTI]

Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source is disclosed. A contamination-free VUV light source having a 225 cm{sup 2} emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm{sup 2} at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing. 3 figs.

Sze, R.C.; Quigley, G.P.

1996-12-17T23:59:59.000Z

157

Advanced Neutron Source (ANS) Project. Progress report FY 1993  

SciTech Connect (OSTI)

This report covers the progress made in 1993 in the following sections: (1) project management; (2) research and development; (3) design and (4) safety. The section on research and development covers the following: (1) reactor core development; (2) fuel development; (3) corrosion loop tests and analysis; (4) thermal-hydraulic loop tests; (5) reactor control and shutdown concepts; (6) critical and subcritical experiments; (7) material data, structure tests, and analysis; (8) cold source development; (9) beam tube, guide, and instrument development; (10) neutron transport and shielding; (11) I and C research and development; and (12) facility concepts.

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

1994-01-01T23:59:59.000Z

158

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

E-Print Network [OSTI]

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

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

2014-01-01T23:59:59.000Z

159

National Synchrotron Light Source II Project Progress Report  

E-Print Network [OSTI]

, power supply procurement, BPM electronics testing, and controls system design. With details of technical'S ASSESSMENT FEBRUARY 2010 OVERALL ASSESSMENT The National Synchrotron Light Source II project maintained excellent technical progress and satisfactory cost and schedule performance. The DOE Independent Project

Ohta, Shigemi

160

Microsoft Word - Science and Technology of Future Light Sources...  

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

0839 BNL-81895-2008 LBNL-1090E-2009 SLAC-R-917 Science and Technology of Future Light Sources A White Paper Report prepared by scientists from ANL, BNL, LBNL and SLAC. The...

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


161

A Next Generation Light Source Facility at LBNL  

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

A Next Generation Light Source Facility at LBNL A Next Generation Light Source Facility at LBNL Author: Corlett, J.N. Publication Date: 04-12-2011 Publication Info: Lawrence Berkeley National Laboratory Permalink: http://escholarship.org/uc/item/81t3h97w Keywords: NGLS, FEL, 2 GeV superconducting linear accelerator, high-brightness, highrepetition- rate, high- repetition-rate (1 MHz) Local Identifier: LBNL Paper LBNL-4391E Preferred Citation:

162

New Directions in X-Ray Light Sources  

ScienceCinema (OSTI)

July 15, 2008 Berkeley Lab lecture: Molecular movies of chemical reactions and material phase transformations need a strobe of x-rays, the penetrating light that reveals how atoms and molecules assemble in chemical and biological systems and complex materials. Roger Falcone, Director of the Advanced Light Source,will discuss a new generation of x ray sources that will enable a new science of atomic dynamics on ultrafast timescales.

Roger Falcone

2010-01-08T23:59:59.000Z

163

Comparative study of energy saving light sources  

Science Journals Connector (OSTI)

Techno-economic performance comparison of compact fluorescent lamps (CFL) with light emitting diodes (LED), electrode less fluorescent lamps (EEFL), fluorescent tubes, incandescent bulbs, photovoltaic (PV) and fiber optic lighting systems was carried out in view of worsening power and energy crisis in Pakistan. Literature survey showed 23W CFL, 21W EEFL, 18W fluorescent tube or 15W LED lamps emit almost same quantity of luminous flux (lumens) as a standard 100W incandescent lamp. All inclusive, operational costs of LED lamps were found 1.21, 1.62. 1.69, 6.46, 19.90 and 21.04 times lesser than fluorescent tubes, CFL, EEFL, incandescent bulbs, fiber optic solar lighting and PV systems, respectively. However, tubes, LED, CFL and EEFL lamps worsen electric power quality of low voltage networks due to high current harmonic distortions (THD) and poor power factors (PF). Fluorescent lamps emit UV and pollute environment by mercury and phosphors when broken or at end of their life cycle. Energy consumption, bio-effects, and environmental concerns prefer LED lamps over phosphor based lamps but power quality considerations prefer EEFL. CFL and EEFL manufacturers claim operating temperatures in range of ?20CLED lamps may be five to ten times higher that high THD and low PF lamps. Choice of a lamp depends upon its current THD, PF, life span, energy consumption, efficiency, efficacy, color rendering index (CRI) and associated physical effects. This work proposes manufacturing and user level innovations to get rid of low PF problems. Keeping in view downside of phosphor based lamps our research concludes widespread adoption of LED lamps. Government and commercial buildings may consider full spectrum hybrid thermal photovoltaic and solar fiber optic illumination systems.

N. Khan; N. Abas

2011-01-01T23:59:59.000Z

164

5 MW pulsed spallation neutron source, Preconceptual design study  

SciTech Connect (OSTI)

This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in {approx} 1 {mu}sec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor the present design approach over the alternative approach pursued elsewhere, whereby use is made of a high energy linear accelerator in conjunction with a dc accumulation ring. With the knowledge that this alternative design is under active development, it was deliberately decided to favor here the low energy linac-fast cycling booster approach. Clearly, the present design, as developed here, must be carried to the full conceptual design stage in order to facilitate a meaningful technology and cost comparison with alternative designs.

Not Available

1994-06-01T23:59:59.000Z

165

Advanced Photon Source, Canadian Light Source Strengthen Ties, Expand X-ray  

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

Rose of APS and CNM One of Four DOE Early Career Award Winners Rose of APS and CNM One of Four DOE Early Career Award Winners Scientists Close-In on Artificial Spider Silk Ekiert Earns 2012 APSUO Franklin Award for Studies of Influenza Virus Clever Apes on WBEZ: Breaking the Fossil Record Gerig to Chair Particle Accelerator School Board APS News Archives: 2012 | 2011 | 2010 | 2009 2008 | 2007 | 2006 | 2005 2004 | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed Advanced Photon Source, Canadian Light Source Strengthen Ties, Expand X-ray Technology and Research JUNE 18, 2012 Bookmark and Share The interiors of the Canadian Light Source (top) and Advanced Photon Source experiment halls. (CLS photo courtesy of Canadian Light Source) Seeking to solve some of today's greatest global problems, scientists using x-ray light source facilities at national research laboratories in

166

National Synchrotron Light Source annual report 1991  

SciTech Connect (OSTI)

This report discusses the following research conducted at NSLS: atomic and molecular science; energy dispersive diffraction; lithography, microscopy and tomography; nuclear physics; UV photoemission and surface science; x-ray absorption spectroscopy; x-ray scattering and crystallography; x-ray topography; workshop on surface structure; workshop on electronic and chemical phenomena at surfaces; workshop on imaging; UV FEL machine reviews; VUV machine operations; VUV beamline operations; VUV storage ring parameters; x-ray machine operations; x-ray beamline operations; x-ray storage ring parameters; superconducting x-ray lithography source; SXLS storage ring parameters; the accelerator test facility; proposed UV-FEL user facility at the NSLS; global orbit feedback systems; and NSLS computer system.

Hulbert, S.L.; Lazarz, N.M. (eds.)

1992-04-01T23:59:59.000Z

167

A Test Beamline on Diamond Light Source  

SciTech Connect (OSTI)

A Test beamline B16 has been built on the 3 GeV Diamond synchrotron radiation source. The beamline covers a wide photon energy range from 2 to 25 keV. The beamline is highly flexible and versatile in terms of the available beam size (a micron to 100 mm) and the range of energy resolution and photon flux; by virtue of its several operational modes, and the different inter-changeable instruments available in the experiments hutch. Diverse experimental configurations can be flexibly configured using a five-circle diffractometer, a versatile optics test bench, and a suite of detectors. Several experimental techniques including reflectivity, diffraction and imaging are routinely available. Details of the beamline and its measured performance are presented.

Sawhney, K. J. S.; Dolbnya, I. P.; Tiwari, M. K.; Alianelli, L.; Scott, S. M.; Preece, G. M.; Pedersen, U. K.; Walton, R. D. [Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, Oxfordshire-OX11 0DE (United Kingdom)

2010-06-23T23:59:59.000Z

168

Neutron generators with size scalability, ease of fabrication and multiple ion source functionalities  

DOE Patents [OSTI]

A neutron generator is provided with a flat, rectilinear geometry and surface mounted metallizations. This construction provides scalability and ease of fabrication, and permits multiple ion source functionalities.

Elizondo-Decanini, Juan M

2014-11-18T23:59:59.000Z

169

Electron cloud instabilities in the Proton Storage Ring and Spallation Neutron Source  

Science Journals Connector (OSTI)

Electron cloud instabilities in the Los Alamos Proton Storage Ring and those foreseen for the Oak Ridge Spallation Neutron Source are examined theoretically, numerically, and experimentally.

M. Blaskiewicz; M. A. Furman; M. Pivi; R. J. Macek

2003-01-21T23:59:59.000Z

170

Design of the Small Angle Neutron Scattering instrument at the Indiana University Low Energy Neutron Source| Applications to the study of nanostructured materials.  

E-Print Network [OSTI]

?? The Low Energy Neutron Source (LENS) located at the Indiana University Cyclotron Facility (IUCF) is a prototypical long-pulse accelerator-based neutron source. The Small Angle (more)

Remmes, Nicholas B.

2008-01-01T23:59:59.000Z

171

CUDA and MPI performances on the computation of Rossi-? distribution from pulsed neutron sources  

Science Journals Connector (OSTI)

Abstract This study presents the methodology to calculate the Rossi-? distribution for a subcritical assembly driven by an external pulsed neutron source through MCNP6 computer simulations. The Rossi-? distribution is obtained from the signal (e.g., 3He(n,p) reactions) of a neutron detector placed in one experimental channel of the subcritical assembly. The detector signal is obtained from MCNP6 computer simulations modeling a single pulse of the external neutron source. The MCNP6 output data for a single pulse of the external neutron source must be processed to take into account the effect of delayed neutrons born in all previous source pulses. The calculation of the Rossi-? distribution from a pulsed neutron source is time consuming because of the huge amount of processed data. Consequently, the algorithms introduced in this work use parallel computing platforms, e.g., CUDA or MPI, to reduce the computing time.

Alberto Talamo

2015-01-01T23:59:59.000Z

172

Optimizing Laser-accelerated Ion Beams for a Collimated Neutron Source  

SciTech Connect (OSTI)

High-flux neutrons for imaging and materials analysis applications have typically been provided by accelerator- and reactor-based neutron sources. A novel approach is to use ultraintense (>1018W/cm2) lasers to generate picosecond, collimated neutrons from a dual target configuration. In this article, the production capabilities of present and upcoming laser facilities are estimated while independently maximizing neutron yields and minimizing beam divergence. A Monte-Carlo code calculates angular and energy distributions of neutrons generated by D-D fusion events occurring within a deuterated target for a given incident beam of D+ ions. Tailoring of the incident distribution via laser parameters and microlens focusing modifies the emerging neutrons. Projected neutron yields and distributions are compared to conventional sources, yielding comparable on-target fluxes per discharge, shorter time resolution, larger neutron energies and greater collimation.

C.L. Ellison and J. Fuchs

2010-09-23T23:59:59.000Z

173

Source Attribution of Light Absorbing Aerosol in Arctic Snow  

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

Source Attribution of Light Absorbing Source Attribution of Light Absorbing Aerosol in Arctic Snow (Preliminary analysis of 2008-2009 data) Outline * Receptor modeling overview * Results from 2007 data set * New goals arising from analysis of 2007 data * New data for 2008 * New data for 2009 * Tentative conclusions * Future analysis i Factor profiles from 2007 analysis Source attribution of Black Carbon from 2007 analysis Goals/Issues suggested by the analysis of the 2007 data set * Are there seasonal differences in the source strengths? * Are there other LAA chemical components besides black carbon. What are their sources? * Can the various data sets available (e.g., 2007, 2008, 2009) be combined in a single large PMF analysis 2008 Data Set For Receptor Analysis * 42 samples from Eastern Siberia including 4 depth profiles

174

Physics data base for the beam plasma neutron source (BPNS)  

SciTech Connect (OSTI)

A 14-MeV deuterium-tritium (D-T) neutron source for accelerated end-of-life testing of fusion reactor materials has been designed on the basis of a linear two-component collisional plasma system. An intense flux (up to 5 {times} 10{sup 18}/m{sup 2}{center dot}s) of 14-MeV neutrons is produced in a fully ionized high-density (n{sub e} {approx equal} 3 {times} 10{sup 21} m{sup {minus}3}) tritium target by transverse injection of 60 MW of neutral beam power. Power deposited in the target is removed by thermal electron conduction to large end chambers, where it is deposited in gaseous plasma collectors. We show in this paper that the major physics issues have now been experimentally demonstrated. These include magnetohydrodynamic (MHD) equilibrium and stability, microstability, startup, fueling, Spitzer electron thermal conductivity, and power deposition in a gaseous plasma collector. However, an integrated system has not been demonstrated. 28 refs., 8 figs., 2 tabs.

Coensgen, F.H.; Casper, T.A.; Correll, D.L.; Damm, C.C.; Futch, A.H.; Molvik, A.W.

1990-10-12T23:59:59.000Z

175

Electron Cloud Mitigation in the Spallation Neutron Source Ring  

SciTech Connect (OSTI)

The Spallation Neutron Source (SNS) accumulator ring is designed to accumulate, via H{sup -} injection, protons of 2 MW beam power at 1 GeV kinetic energy at a repetition rate of 60 Hz [1]. At such beam intensity, electron-cloud is expected to be one of the intensity-limiting mechanisms that complicate ring operations. This paper summarizes mitigation strategy adopted in the design, both in suppressing electron-cloud formation and in enhancing Landau damping, including tapered magnetic field and monitoring system for the collection of stripped electrons at injection, TiN coated beam chamber for suppression of the secondary yield, clearing electrodes dedicated for the injection region and parasitic on BPMs around the ring, solenoid windings in the collimation region, and planning of vacuum systems for beam scrubbing upon operation.

Wei, J.; Blaskiewicz, Michael; Brodowski, J.; Cameron, P.; Davino, Daniele; Fedotov, A.; He, P.; Hseuh, H.; Lee, Y.Y.; Ludewig, H.; Meng, W.; Raparia, D.; Tuozzolo, J.; Zhang, S.Y.; Catalan-Lasheras, N.; Macek, R.J.; Furman, Miguel A.; Aleksandrov, A.; Cousineau, S.; Danilov, V.; Henderson, S.; /Brookhaven /CERN /LANL, Ctr. for Nonlinear Studies /LBL, Berkeley /Oak Ridge /SLAC

2008-03-17T23:59:59.000Z

176

Theoretical investigation of a tunable free-electron light source  

SciTech Connect (OSTI)

The concept and experimental results of a light source given in a recent paper by Adamo et al.[Phys. Rev. Lett. 103, 113901 (2009)] are very interesting and attractive. Our paper presents detailed theoretical investigations on such a light source, and our results confirm that the mechanism of the light radiation experimentally detected in the published paper is a special kind of diffraction radiation in a waveguide with nanoscale periodic structure excited by an electron beam. The numerical calculations based on our theory and digital simulations agree well with the experimental results. This mechanism of diffraction radiation is of significance in physics and optics, and may bring good opportunities for the generation of electromagnetic waves from terahertz to light frequency regimes.

Liu Shenggang; Hu Min; Zhang Yaxin; Liu Weihao; Zhang Ping; Zhou Jun [Terahertz Research Center, University of Electronic Science and Technology of China, Chengdu 610054 (China)

2011-06-15T23:59:59.000Z

177

Theoretical investigation of a tunable free-electron light source  

Science Journals Connector (OSTI)

The concept and experimental results of a light source given in a recent paper by Adamo et al. [Phys. Rev. Lett. 103, 113901 (2009)] are very interesting and attractive. Our paper presents detailed theoretical investigations on such a light source, and our results confirm that the mechanism of the light radiation experimentally detected in the published paper is a special kind of diffraction radiation in a waveguide with nanoscale periodic structure excited by an electron beam. The numerical calculations based on our theory and digital simulations agree well with the experimental results. This mechanism of diffraction radiation is of significance in physics and optics, and may bring good opportunities for the generation of electromagnetic waves from terahertz to light frequency regimes.

Shenggang Liu; Min Hu; Yaxin Zhang; Weihao Liu; Ping Zhang; Jun Zhou

2011-06-30T23:59:59.000Z

178

Light Sources Help Discover New Drug Against Melanoma | Department of  

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

Light Sources Help Discover New Drug Against Melanoma Light Sources Help Discover New Drug Against Melanoma Light Sources Help Discover New Drug Against Melanoma July 18, 2011 - 12:07pm Addthis The new anti-cancer drug, vemurafenib, is the green honeycomb structure at middle left. Four dotted red lines show where it attaches to a target area in the mutated enzyme, disabling it from promoting the growth of tumors. | Image courtesy of Plexxikon Inc. The new anti-cancer drug, vemurafenib, is the green honeycomb structure at middle left. Four dotted red lines show where it attaches to a target area in the mutated enzyme, disabling it from promoting the growth of tumors. | Image courtesy of Plexxikon Inc. Mike Ross Science Writer at SLAC National Accelerator Laboratory What does this mean for me? A new drug designed to fight melanoma was discovered thanks to the

179

GE Uses DOE Advanced Light Sources to Develop Revolutionary Battery  

Office of Science (SC) Website

GE Uses DOE Advanced Light Sources to Develop GE Uses DOE Advanced Light Sources to Develop Revolutionary Battery Technology Discovery & Innovation Stories of Discovery & Innovation Brief Science Highlights SBIR/STTR Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 06.13.11 GE Uses DOE Advanced Light Sources to Develop Revolutionary Battery Technology Company is constructing a new battery factory in Upstate New York that is expected to create 300+ jobs. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo GE's new Image courtesy of GE GE's new "Durathon(tm)" sodium metal halide battery. The story of American manufacturing over the past two decades has too often been a tale of outsourcing, off-shoring, and downsizing-not least in

180

Structural biology research at the National Synchroton Light Source  

SciTech Connect (OSTI)

The world`s foremost facility for scientific research using x-rays and ultraviolet and infrared radiation is operated by the national synchrotron Light Source Department. This year alone, a total of 2200 guest researchers performed experiments at the world`s largest source of synchrotron light. Researchers are trying to define the three- dimensional structures of biological macromolecules to create a map of life, a guide for exploring the biological and chemical interactions of the vast variety of molecules found in living organisms. Studies in structural biology may lead to new insights into how biological systems are formed and nourished, how they survive and grow, how they are damaged and die. This document discusses some the the structural biological research done at the National Synchrotron Light Source.

NONE

1996-05-01T23:59:59.000Z

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


181

Synchrotron radiation as a light source in confocal microscopy  

Science Journals Connector (OSTI)

The optical properties of a confocal scanning microscope that was designed to utilize a synchrotron as light source are presented. The usable spectral range is from 200 nm up to 700 nm. Using 325?nm laser light it is shown that the lateral resolution is about 125 nm and the axial resolution better than 250 nm. After transport of the microscope from Utrecht to the Daresbury Synchrotron Source 200?nm excitation can be applied and the lateral resolution will drop to below 100 nm.

C. J. R. van der Oord; H. C. Gerritsen; Y. K. Levine; W. J. Myring; G. R. Jones; I. H. Munro

1992-01-01T23:59:59.000Z

182

Lujan Neutron Scattering Center (Lujan Center) | U.S. DOE Office...  

Office of Science (SC) Website

Lujan Neutron Scattering Center (Lujan Center) Scientific User Facilities (SUF) Division SUF Home About User Facilities User Facilities Dev X-Ray Light Sources Neutron Scattering...

183

Neutron Scattering Facilities | U.S. DOE Office of Science (SC...  

Office of Science (SC) Website

Neutron Scattering Facilities Scientific User Facilities (SUF) Division SUF Home About User Facilities User Facilities Dev X-Ray Light Sources Neutron Scattering Facilities High...

184

Neutron flux and energy characterization of a plutonium-beryllium isotopic neutron source by Monte Carlo simulation with verification by neutron activation analysis.  

E-Print Network [OSTI]

??The purpose of this research was to characterize the neutron energy distribution and flux emitted from the UNLV plutonium-beryllium source, serial number MRC-N-W PuBe 453. (more)

Harvey, Zachary R

2010-01-01T23:59:59.000Z

185

Spallation-Driven Cold Neutron Sources Dr. Bradley J. Micklich  

E-Print Network [OSTI]

Neutrons were produced by spallation/fission by 450MeV protons striking depleted uranium target Proton

McDonald, Kirk

186

Advanced Light Source Activity Report 1997/1998  

SciTech Connect (OSTI)

This Lawrence Berkeley National Laboratory, Advanced Light Source (ALS) activity report for 1997/98 discusses the following topics: Introduction and Overview; Science Highlights; Facility Report; Special Events; ALS Advisory Panels 1997/98; ALS Staff 1997/98 and Facts and Figures for the year.

Greiner, Annette (ed.)

1999-03-01T23:59:59.000Z

187

Superconducting RF Linac Technology for ERL Light Sources  

SciTech Connect (OSTI)

Energy Recovering Linacs (ERLs) offer an attractive alternative as drivers for light sources as they combine the desirable characteristics of both storage rings (high efficiency) and linear accelerators (superior beam quality). Using superconducting RF technology allows ERLs to operate more efficiently because of the inherent characteristics of SRF linacs, namely that they are high gradient-low impedance structures and their ability to operate in the long pulse or CW regime. We present an overview of the physics challenges encountered in the design and operation of ERL based light sources with particular emphasis on those issues related to SRF technology. These challenges include maximizing a cavity???????¢????????????????s Qo to increase cryogenic efficiency, maintaining control of the cavity field in the presence of the highest feasible loaded Q and providing adequate damping of the higher-order modes (HOMs). If not sufficiently damped, dipole HOMs can drive the multipass beam breakup (BBU) instability which ERLs are particularly susceptible to. Another challenge involves efficiently extracting the potentially large amounts of HOM power that are generated when a bunch traverses the SRF cavities and which may extend over a high range of frequencies. We present experimental data from the Jefferson Lab FEL Upgrade, a 10 mA ERL light source presently in operation, aimed at addressing some of these issues. We conclude with an outlook towards the future of ERL based light sources.

Chris Tennant

2005-08-01T23:59:59.000Z

188

Photonic crystal fibre-based light source for STED lithography  

SciTech Connect (OSTI)

A light source having a relative noise level in the order of 10{sup -6} and sufficient stability for application in STED lithography has been obtained using the generation of Cherenkov peaks in a supercontinuum spectrum. (laser applications and other topics in quantum electronics)

Glubokov, D A; Sychev, V V; Vitukhnovsky, Alexey G; Korol'kov, A E

2013-06-30T23:59:59.000Z

189

Advanced Photon Source (APS) | U.S. DOE Office of Science (SC...  

Office of Science (SC) Website

Syncrotron Light Source (NSLS-II) Stanford Synchrotron Radiation Light Source (SSRL) Neutron Scattering Facilities Nanoscale Science Research Centers (NSRCs) Projects...

190

Photon Sciences | Operating the National Synchrotron Light Source,  

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

Industrial Collaborators Industrial Collaborators The National Synchrotron Light Source (NSLS) and its future successor, NSLS-II, can help companies large and small solve research and manufacturing problems, generate new technologies and products, and stay competitive. The Photon Sciences Directorate would like to encourage greater use of its facilities by industrial researchers and facilitate collaborations between industry and NSLS staff, as well as government and academic institutions. Synchrotron Use by Industry What is a synchrotron? A synchrotron light source is a large machine that produces intense beams of infrared, ultraviolet, and x-ray light for the study of substances at very small scales, from looking at the molecular structure of proteins to probing the electronic properties of the next generation of computer-chip

191

National Synchrotron Light Source annual report 1991. Volume 2, October 1, 1990--September 30, 1991  

SciTech Connect (OSTI)

This report contains abstracts from research conducted at the national synchrotron light source. (LSP)

Hulbert, S.L.; Lazarz, N.N. [eds.

1992-04-01T23:59:59.000Z

192

Lighting Group: Sources and Ballasts: LED Reflector Lamp  

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

LED Reflector Lamp LED Reflector Lamp LED Reflector Lamp Objective LED reflector lamp The goal of this project is to develop a revolutionary new reflector lamp which offers many advantages over current incandescent reflector lamps, including: three times greater efficiency ten times the rated life greater optical and performance properties use of light emitting diodes (LEDs) to generate the light. Although LEDs have been commercially available since the late 1960’s, recent dramatic improvements in LED technology have led to white light devices with efficiencies that meet or exceed those of a standard incandescent lamp. This project will build upon these improvements to develop a new type of source for focusing light. Contact Information For more information on this project, please contact:

193

NSLS II: The Future National Synchrotron Light Source  

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

2011 Call for Beamline Development Proposals 2011 Call for Beamline Development Proposals National Synchrotron Light Source II February 16, 2011 NSLS-II Rendering Critical Dates Call for proposal issued Thursday, February 17, 2011 Letter of Intent due Monday, March 28, 2011 (submitted LOIs) Beamline development workshops April-June 2011 Beamline proposal due Monday, July 25, 2011 Related Materials Proposal template NSLS-II Beamline Development Policy NSLS-II Source Properties NSLS-II User Access Policy Project Beamlines Background Beamline Information Approved Proposals From 2010 The National Synchrotron Light Source II (NSLS-II), currently under construction at the U.S. Department of Energys Brookhaven National Laboratory on Long Island, NY, is pleased to announce the 2011 Call for Beamline Development Proposals for experimental facilities to be implemented at NSLS-II.

194

The Neutron Energy Spectrum Study from the Phase II Solid Methane Moderator at the LENS Neutron Source  

E-Print Network [OSTI]

Neutron energy spectrum measurements from a solid methane moderator were performed at the Low Energy Neutron Source (LENS) at Indiana University Cyclotron Facility (IUCF) to verify our neutron scattering model of solid methane. The time-of-flight method was used to measure the energy spectrum of the moderator in the energy range of 0.1$meV\\sim$ 1$eV$. Neutrons were counted with a high efficiency $^{3}{He}$ detector. The solid methane moderator was operated in phase II temperature and the energy spectra were measured at the temperatures of 20K and 4K. We have also tested our newly-developed scattering kernels for phase II solid methane by calculating the neutron spectral intensity expected from the methane moderator at the LENS neutron source using MCNP (Monte Carlo N-particle Transport Code). Within the expected accuracy of our approximate approach, our model predicts both the neutron spectral intensity and the optimal thickness of the moderator at both temperatures. The predictions are compared to the measured energy spectra. The simulations agree with the measurement data at both temperatures.

Yunchang Shin; W. Mike Snow; Christopher M. Lavelle; David V. Baxter; Xin Tong; Haiyang Yan; Mark Leuschner

2007-11-19T23:59:59.000Z

195

Advanced neutron source reactor probabilistic flow blockage assessment  

SciTech Connect (OSTI)

The Phase I Level I Probabilistic Risk Assessment (PRA) of the conceptual design of the Advanced Neutron Source (ANS) Reactor identified core flow blockage as the most likely internal event leading to fuel damage. The flow blockage event frequency used in the original ANS PRA was based primarily on the flow blockage work done for the High Flux Isotope Reactor (HFIR) PRA. This report examines potential flow blockage scenarios and calculates an estimate of the likelihood of debris-induced fuel damage. The bulk of the report is based specifically on the conceptual design of ANS with a 93%-enriched, two-element core; insights to the impact of the proposed three-element core are examined in Sect. 5. In addition to providing a probability (uncertainty) distribution for the likelihood of core flow blockage, this ongoing effort will serve to indicate potential areas of concern to be focused on in the preliminary design for elimination or mitigation. It will also serve as a loose-parts management tool.

Ramsey, C.T.

1995-08-01T23:59:59.000Z

196

Fuel qualification plan for the Advanced Neutron Source Reactor  

SciTech Connect (OSTI)

This report describes the development and qualification plan for the fuel for the Advanced Neutron Source. The reference fuel is U{sub 3}Si{sub 2}, dispersed in aluminum and clad in 6061 aluminum. This report was prepared in May 1994, at which time the reference design was for a two-element core containing highly enriched uranium (93% {sup 235}U) . The reactor was in the process of being redesigned to accommodate lowered uranium enrichment and became a three-element core containing a higher volume fraction of uranium enriched to 50% {sup 235}U. Consequently, this report was not issued at that time and would have been revised to reflect the possibly different requirements of the lower-enrichment, higher-volume fraction fuel. Because the reactor is now being canceled, this unrevised report is being issued for archival purposes. The report describes the fabrication and inspection development plan, the irradiation tests and performance modeling to qualify performance, the transient testing that is part of the safety program, and the interactions and interfaces of the fuel development with other tasks.

Copeland, G.L.

1995-07-01T23:59:59.000Z

197

Fabrication development for the Advanced Neutron Source Reactor  

SciTech Connect (OSTI)

This report presents the fuel fabrication development for the Advanced Neutron Source (ANS) reactor. The fuel element is similar to that successfully fabricated and used in the High Flux Isotope Reactor (HFIR) for many years, but there are two significant differences that require some development. The fuel compound is U{sub 3}Si{sub 2} rather than U{sub 3}O{sub 8}, and the fuel is graded in the axial as well as the radial direction. Both of these changes can be accomplished with a straightforward extension of the HFIR technology. The ANS also requires some improvements in inspection technology and somewhat more stringent acceptance criteria. Early indications were that the fuel fabrication and inspection technology would produce a reactor core meeting the requirements of the ANS for the low volume fraction loadings needed for the highly enriched uranium design (up to 1.7 Mg U/m{sup 3}). Near the end of the development work, higher volume fractions were fabricated that would be required for a lower- enrichment uranium core. Again, results look encouraging for loadings up to {approx}3.5 Mg U/m{sup 3}; however, much less evaluation was done for the higher loadings.

Pace, B.W. [Babcock and Wilcox, Lynchburg, VA (United States); Copeland, G.L. [Oak Ridge National Lab., TN (United States)

1995-08-01T23:59:59.000Z

198

DOE Science Showcase - Neutron Sources for Studying Matter |...  

Office of Scientific and Technical Information (OSTI)

(DOE) Office of Basic Energy Sciences. This activity supports the operation of three neutron scattering facilities, one of the most powerful tools for characterizing matter....

199

The advanced light source: America`s brightest light for science and industry  

SciTech Connect (OSTI)

America`s brightest light comes from the Advanced Light Source (ALS), a national facility for scientific research, product development, and manufacturing. Completed in 1993, the ALS produces light in the ultraviolet and x-ray regions of the spectrum. Its extreme brightness provides opportunities for scientific and technical progress not possible anywhere else. Technology is poised on the brink of a major revolution - one in which vital machine components and industrial processes will be drastically miniaturized. Industrialized nations are vying for leadership in this revolution - and the huge economic rewards the leaders will reap.

Cross, J.; Lawler, G.

1994-03-01T23:59:59.000Z

200

H{sup -} radio frequency source development at the Spallation Neutron Source  

SciTech Connect (OSTI)

The Spallation Neutron Source (SNS) now routinely operates nearly 1 MW of beam power on target with a highly persistent {approx}38 mA peak current in the linac and an availability of {approx}90%. H{sup -} beam pulses ({approx}1 ms, 60 Hz) are produced by a Cs-enhanced, multicusp ion source closely coupled with an electrostatic low energy beam transport (LEBT), which focuses the 65 kV beam into a radio frequency quadrupole accelerator. The source plasma is generated by RF excitation (2 MHz, {approx}60 kW) of a copper antenna that has been encased with a thickness of {approx}0.7 mm of porcelain enamel and immersed into the plasma chamber. The ion source and LEBT normally have a combined availability of {approx}99%. Recent increases in duty-factor and RF power have made antenna failures a leading cause of downtime. This report first identifies the physical mechanism of antenna failure from a statistical inspection of {approx}75 antennas which ran at the SNS, scanning electron microscopy studies of antenna surface, and cross sectional cuts and analysis of calorimetric heating measurements. Failure mitigation efforts are then described which include modifying the antenna geometry and our acceptance/installation criteria. Progress and status of the development of the SNS external antenna source, a long-term solution to the internal antenna problem, are then discussed. Currently, this source is capable of delivering comparable beam currents to the baseline source to the SNS and, an earlier version, has briefly demonstrated unanalyzed currents up to {approx}100 mA (1 ms, 60 Hz) on the test stand. In particular, this paper discusses plasma ignition (dc and RF plasma guns), antenna reliability, magnet overheating, and insufficient beam persistence.

Welton, R. F.; Gawne, K. R.; Han, B. X.; Murray, S. N.; Pennisi, T. R.; Roseberry, R. T.; Santana, M.; Stockli, M. P. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37830-6471 (United States); Dudnikov, V. G. [Muons, Inc., 552 N. Batavia Avenue, Batavia, Illinois 60510 (United States); Turvey, M. W. [Villanova University, 800E. Lancaster Ave, Villanova, Pennsylvania 19085 (United States)

2012-02-15T23:59:59.000Z

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


201

Neutron economic reactivity control system for light water reactors  

DOE Patents [OSTI]

A neutron reactivity control system for a LWBR incorporating a stationary seed-blanket core arrangement. The core arrangement includes a plurality of contiguous hexagonal shaped regions. Each region has a central and a peripheral blanket area juxapositioned an annular seed area. The blanket areas contain thoria fuel rods while the annular seed area includes seed fuel rods and movable thoria shim control rods.

Luce, Robert G. (Glenville, NY); McCoy, Daniel F. (Latham, NY); Merriman, Floyd C. (Rotterdam, NY); Gregurech, Steve (Scotia, NY)

1989-01-01T23:59:59.000Z

202

Insertion devices for the Advanced Light Source at LBL  

SciTech Connect (OSTI)

The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory will be the first of the new generation of dedicated synchrotron light sources to be put into operation. Specially designed insertion devices will be required to realize the high brightness photon beams made possible by the low emittance of the electron beam. The complement of insertion devices on the ALS will include undulators with periods as short as 3.9 cm and one or more high field wigglers. The first device to be designed is a 5 m long, 5 cm period, hybrid undulator. The goal of very high brightness and high harmonic output imposes unusually tight tolerances on the magnetic field quality and thus on the mechanical structure. The design process, using a generic structure for all undulators, is described. 5 refs., 4 figs., 1 tab.

Hassenzahl, W.; Chin, J.; Halbach, K.; Hoyer, E.; Humphries, D.; Kincaid, B.; Savoy, R.

1989-03-01T23:59:59.000Z

203

Fabrication and characterization of the source grating for visibility improvement of neutron phase imaging with gratings  

SciTech Connect (OSTI)

The fabrication of gratings including metal deposition processes for highly neutron absorbing lines is a critical issue to achieve a good visibility of the grating-based phase imaging system. The source grating for a neutron Talbot-Lau interferometer is an array of Gadolinium (Gd) structures that are generally made by sputtering, photo-lithography, and chemical wet etching. However, it is very challenging to fabricate a Gd structure with sufficient neutron attenuation of approximately more than 20 {mu}m using a conventional metal deposition method because of the slow Gd deposition rate, film stress, high material cost, and so on. In this article, we fabricated the source gratings for neutron Talbot-Lau interferometers by filling the silicon structure with Gadox particles. The new fabrication method allowed us a very stable and efficient way to achieve a much higher Gadox filled structure than a Gd film structure, and is even more suitable for thermal polychromatic neutrons, which are more difficult to stop than cold neutrons. The newly fabricated source gratings were tested at the polychromatic thermal neutron grating interferometer system of HANARO at the Korea Atomic Energy Research Institute, and the visibilities and images from the neutron phase imaging system with the new source gratings were compared with those fabricated by a Gd deposition method.

Kim, Jongyul [Neutron Science Division, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Nuclear and Quantum Engineering Department, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Lee, Kye Hong; Lim, Chang Hwy; Kim, Taejoo [Neutron Science Division, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Ahn, Chi Won [Nano Fusion Technology Division, National Nanofab Center, Daejeon 305-701 (Korea, Republic of); Cho, Gyuseong [Nuclear and Quantum Engineering Department, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Lee, Seung Wook [School of Mechanical Engineering, Pusan National University, Pusan 609-735 (Korea, Republic of)

2013-06-15T23:59:59.000Z

204

Intense Pulsed Neutron Source progress report for 1991  

SciTech Connect (OSTI)

The IPNS Progress Report 10th Anniversary Edition is being published in recognition of the first ten years of successful IPNS operation. To emphasize the significance of this milestone, we wanted this report to stand apart from the previous IPNS Progress Reports, and the best way to do this, we thought, was to make the design and organization of the report significantly different. In their articles, authors were asked to emphasize not only advances made since IPNS began operating but also the groundwork that was laid at its predecessor facilities - Argonne's ZING-P and ZING-P' prototype pulsed neutron sources and CP-5 reactor. Each article stands as a separate chapter in the report, since each represents a particular instrument or class of instruments, system, technique, or area of research. In some cases, contributions were similar to review articles in scientific journals, complete with extensive lists of references. Ten-year cumulative lists of members of IPNS committees and of scientists who have visited or done experiments at IPNS were assembled. A list of published and in press'' articles in journals, books, and conference proceedings, resulting from work done at IPNS during the past ten years, was compiled. And archival photographs of people and activities during the ten-year history of IPNS were located and were used liberally throughout the report. The titles of the chapters in this report are: accelerator; computer; radiation effects; powder; stress; single crystal; superconductivity; amorphous; small angle; reflection; quasielastic; inelastic; inelastic magnetic; deep inelastic; user program; the future; and publications.

Not Available

1991-01-01T23:59:59.000Z

205

Designing and testing the neutron source deployment system and calibration plan for a dark matter detector  

E-Print Network [OSTI]

In this thesis, we designed and tested a calibration and deployment system for the MiniCLEAN dark matter detector. The deployment system uses a computer controlled winch to lower a canister containing a neutron source into ...

Westerdale, Shawn (Shawn S.)

2011-01-01T23:59:59.000Z

206

Concept of the divertor of a fusion neutron source based on a spherical tokamak  

Science Journals Connector (OSTI)

A concept of the divertor and the technology for organizing the edge plasma in a fusion neutron source based on a spherical tokamak (FNS-ST) are described. The experimental data on the characteristics of the p...

V. Yu. Sergeev; B. V. Kuteev; A. S. Bykov; V. S. Petrov

2012-07-01T23:59:59.000Z

207

Neutron kinetics in subcritical cores with application to the source modulation method  

E-Print Network [OSTI]

Neutron kinetics in subcritical cores with application to the source modulation method J. Wright for the measurement of reactivity in subcritical, source-driven cores. Methods of measuring reactivity by a single. Hence, first, the conditions of point kinetic behaviour in subcritical source-driven cores are revis

Pázsit, Imre

208

The performance of reflectometers at continuous wave and pulsed-neutron sources  

SciTech Connect (OSTI)

To quantify gains from time-of-flight (TOF) methods, identical reflectometers viewing a continuous wave (CW) neutron source and a variety of pulsed-neutron sources were simulated using a Monte Carlo technique. Reflectivity profiles obtained for a simple thin-film, reflecting,sample were nearly identical in all simulations, and models fitted to the simulated data yielded parameters (film thickness, surface roughness, and scattering length density) that were equally accurate and precise in all cases. The simulations confirm the power of the TOF method and demonstrate that the performance of pulsed sources for reflectometry does not scale simply as the inverse duty factor of the source. In the case of long-pulse sources, the simulations suggest that pulse tails have little effect on results obtained from specular reflectometry and that maximum brightness of the neutron source should be the primary design criterion.

Fritzsimmons, M.R.; Pynn, R.

1995-12-01T23:59:59.000Z

209

Estimation of low-level neutron dose-equivalent rate by using extrapolation method for a curie level AmBe neutron source  

Science Journals Connector (OSTI)

Abstract Neutron radiation protection is an important research area because of the strong radiation biological effect of neutron field. The radiation dose of neutron is closely related to the neutron energy, and the connected relationship is a complex function of energy. For the low-level neutron radiation field (e.g. the AmBe source), the commonly used commercial neutron dosimeter cannot always reflect the low-level dose rate, which is restricted by its own sensitivity limit and measuring range. In this paper, the intensity distribution of neutron field caused by a curie level AmBe neutron source was investigated by measuring the count rates obtained through a 3He proportional counter at different locations around the source. The results indicate that the count rates outside of the source room are negligible compared with the count rates measured in the source room. In the source room, 3He proportional counter and neutron dosimeter were used to measure the count rates and dose rates respectively at different distances to the source. The results indicate that both the count rates and dose rates decrease exponentially with the increasing distance, and the dose rates measured by a commercial dosimeter are in good agreement with the results calculated by the Geant4 simulation within the inherent errors recommended by ICRP and IEC. Further studies presented in this paper indicate that the low-level neutron dose equivalent rates in the source room increase exponentially with the increasing low-energy neutron count rates when the source is lifted from the shield with different radiation intensities. Based on this relationship as well as the count rates measured at larger distance to the source, the dose rates can be calculated approximately by the extrapolation method. This principle can be used to estimate the low level neutron dose values in the source room which cannot be measured directly by a commercial dosimeter.

Gang Li; Jiayun Xu; Jie Zhang

2015-01-01T23:59:59.000Z

210

Characterization of a novel, short pulse laser-driven neutron source  

SciTech Connect (OSTI)

We present a full characterization of a short pulse laser-driven neutron source. Neutrons are produced by nuclear reactions of laser-driven ions deposited in a secondary target. The emission of neutrons is a superposition of an isotropic component into 4? and a forward directed, jet-like contribution, with energies ranging up to 80 MeV. A maximum flux of 4.4 10{sup 9} neutrons/sr has been observed and used for fast neutron radiography. On-shot characterization of the ion driver and neutron beam has been done with a variety of different diagnostics, including particle detectors, nuclear reaction, and time-of-flight methods. The results are of great value for future optimization of this novel technique and implementation in advanced applications.

Jung, D.; Falk, K.; Guler, N.; Devlin, M.; Favalli, A.; Fernandez, J. C.; Gautier, D. C.; Haight, R.; Hamilton, C. E.; Hegelich, B. M.; Johnson, R. P.; Merrill, F.; Schoenberg, K.; Shimada, T.; Taddeucci, T.; Tybo, J. L.; Wender, S. A.; Wilde, C. H.; Wurden, G. A. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Deppert, O. [Technische Universitt Darmstadt, 64289 Darmstadt (Germany)] [Technische Universitt Darmstadt, 64289 Darmstadt (Germany); and others

2013-05-15T23:59:59.000Z

211

Accelerator based neutron source for neutron capture therapy B. Bayanov, Yu. Belchenko, V. Belov, V. Davydenko, A. Donin, A. Dranichnikov, A. Ivanov,  

E-Print Network [OSTI]

approach is based upon vacuum insulation tandem accelerator (VITA) and near threshold 7 Li(p,n)7 Be neutron Fig. 1. Negative hydrogen ion beam is injected into electrostatic vacuum insulation tandem acceleratorAccelerator based neutron source for neutron capture therapy B. Bayanov, Yu. Belchenko, V. Belov, V

Taskaev, Sergey Yur'evich

212

Colossal Light-Induced Refractive-Index Modulation for Neutrons in Holographic Polymer-Dispersed Liquid Crystals  

SciTech Connect (OSTI)

We report strong diffraction of cold neutrons from an only 30 {mu}m thick holographic polymer-dispersed liquid crystal (H-PDLC) transmission grating. The light-induced refractive-index modulation for neutrons is about 10{sup -6}, i.e., nearly 2 orders of magnitude larger than in the best photo-neutron-refractive materials probed up to now. This makes H-PDLCs a promising candidate for fabricating neutron-optical devices.

Fally, Martin; Ellabban, Mostafa A. [Nonlinear Physics Group, Faculty of Physics, Universitaet Wien, Boltzmanngasse 5, A-1090 Vienna (Austria); Drevensek-Olenik, Irena [Nonlinear Physics Group, Faculty of Physics, Universitaet Wien, Boltzmanngasse 5, A-1090 Vienna (Austria); Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, and J. Stefan Institute, Jamova 39, SI 1001 Ljubljana (Slovenia); Pranzas, Klaus P.; Vollbrandt, Juergen [GKSS Forschungszentrum, D-21502 Geesthacht (Germany)

2006-10-20T23:59:59.000Z

213

Radionuclide neutron sources in calibration laboratoryneutron and gamma doses and their changes in time  

Science Journals Connector (OSTI)

......radiation require the determination of this component...been applied for the determination of neutron ambient...equivalent rate and for the determination of neutron and gamma...nominal decay of the main isotope. After 15-20 y...blocks, enclosing the boron or helium proportional......

K. Jzefowicz; N. Golnik; P. Tulik; M. Zielczynski

2007-08-01T23:59:59.000Z

214

Vibrational spectra of light and heavy water with application to neutron cross section calculations  

SciTech Connect (OSTI)

The design of nuclear reactors and neutron moderators require a good representation of the interaction of low energy (E < 1 eV) neutrons with hydrogen and deuterium containing materials. These models are based on the dynamics of the material, represented by its vibrational spectrum. In this paper, we show calculations of the frequency spectrum for light and heavy water at room temperature using two flexible point charge potentials: SPC-MPG and TIP4P/2005f. The results are compared with experimental measurements, with emphasis on inelastic neutron scattering data. Finally, the resulting spectra are applied to calculation of neutron scattering cross sections for these materials, which were found to be a significant improvement over library data.

Damian, J. I. Marquez; Granada, J. R. [Neutron Physics Department and Instituto Balseiro, Centro Atomico Bariloche, CNEA (Argentina); Malaspina, D. C. [Department of Biomedical Engineering and Chemistry of Life Processes Institute, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208 (United States)

2013-07-14T23:59:59.000Z

215

Materials irradiation subpanel report to BESAC neutron sources and research panel  

SciTech Connect (OSTI)

The future success of the nuclear power option in the US (fission and fusion) depends critically on the continued existence of a healthy national materials-irradiation program. Consideration of the requirements for acceptable materials-irradiation systems in a new neutron source has led the subcommittee to identify an advanced steady-state reactor (ANS) as a better choice than a spallation neutron source. However, the subcommittee also hastens to point out that the ANS cannot stand alone as the nation`s sole high-flux mixed-spectrum neutron irradiation source in the next century. It must be incorporated in a broader program that includes other currently existing neutron irradiation facilities. Upgrading and continuing support for these facilities must be planned. In particular, serious consideration should be given to converting the HFIR into a dedicated materials test reactor, and long-term support for several university reactors should be established.

Birtcher, R.C. [Argonne National Lab., IL (United States); Goland, A.N. [Brookhaven National Lab., Upton, NY (United States); Lott, R. [Westinghouse Electric Corp., Pittsburgh, PA (United States). Science and Technology Center; Odette, G.R. [California Univ., Santa Barbara, CA (United States)

1992-09-10T23:59:59.000Z

216

6 GeV light source project cost estimating procedure  

SciTech Connect (OSTI)

To maintain uniformity in estimating the cost requirements of the various components of the 6 GeV Light Source, the following procedure will be used by all the task groups. The procedure uses a Work Breakdown Structure (VBS) to break down the project into manageable, easy to estimate, components. The project is first broken down into major tasks or categories. Then each major division is continuously subdivided until the desired level of detail is achieved. This can be shown best by using the example of the WBS of the Aladdin Upgrade Project, excerpts of which are included in Appendix A.

NONE

1985-10-23T23:59:59.000Z

217

Energy Secretary Moniz Dedicates the Worlds Brightest Synchrotron Light Source  

Broader source: Energy.gov [DOE]

U.S. Department of Energy (DOE) Secretary Ernest Moniz today dedicated the worlds most advanced light source, the National Synchrotron Light Source II (NSLS-II) at Brookhaven National Laboratory (BNL).

218

Inverse free electron laser accelerator for advanced light sources  

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

We discuss the inverse free electron laser (IFEL) scheme as a compact high gradient accelerator solution for driving advanced light sources such as a soft x-ray free electron laser amplifier or an inverse Compton scattering based gamma-ray source. In particular, we present a series of new developments aimed at improving the design of future IFEL accelerators. These include a new procedure to optimize the choice of the undulator tapering, a new concept for prebunching which greatly improves the fraction of trapped particles and the final energy spread, and a self-consistent study of beam loading effects which leads to an energy-efficient high laser-to-beam power conversion.

Duris, J. P.; Musumeci, P.; Li, R. K.

2012-06-01T23:59:59.000Z

219

PHOTOINJECTED ENERGY RECOVERY LINAC UPGRADE FOR THE NATIONAL SYNCHROTRON LIGHT SOURCE *  

E-Print Network [OSTI]

PHOTOINJECTED ENERGY RECOVERY LINAC UPGRADE FOR THE NATIONAL SYNCHROTRON LIGHT SOURCE * Ilan Ben of the National Synchrotron Light Source (NSLS). This upgrade will be based on the Photoinjected Energy Recovering limitations. First, the emittance of a storage ring based light source is proportional to the energy

Brookhaven National Laboratory

220

Modified big bang nucleosynthesis with non-standard neutron sources  

E-Print Network [OSTI]

During big bang nucleosynthesis, any injection of extra neutrons around the time of the $^7$Be formation, i.e. at a temperature of order $T \\simeq 50$~keV, can reduce the predicted freeze-out amount of $^7$Be + $^7$Li that otherwise remains in sharp contradiction with the Spite plateau value inferred from the observations of Pop II stars. However, the growing confidence in the primordial D/H determinations puts a strong constraint on any such scenario. We address this issue in detail, analyzing different temporal patterns of neutron injection, such as decay, annihilation, resonant annihilation, and oscillation between mirror and standard model world neutrons. For this latter case, we derive the realistic injection pattern taking into account thermal effects (damping and refraction) in the primordial plasma. If the extra neutron supply is the sole non-standard mechanism operating during the BBN, the suppression of lithium abundance below Li/H~$\\leq 1.9 \\times 10^{-10}$ always leads to the overproduction of deuterium, D/H~$\\geq 3.6 \\times 10^{-5}$, well outside the error bars suggested by recent observations.

Alain Coc; Maxim Pospelov; Jean-Philippe Uzan; Elisabeth Vangioni

2014-05-07T23:59:59.000Z

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


221

RESULTS OF FIRST EXPERIMENTS ON NEUTRON GENERATION IN THE VITA NEUTRON SOURCE  

E-Print Network [OSTI]

as activation detector due to capture of epithermal neutrons by iodine also. Bubble detectors were used shell and reliably protected from magnetic fields and electromagnetic noises. Stability of the power

Taskaev, Sergey Yur'evich

222

Consideration of a ultracold neutron source in two-dimensional cylindrical geometry by taking simulated boundaries  

SciTech Connect (OSTI)

A new idea to calculate ultracold neutron (UCN) production by using Monte Carlo simulation method to calculate the cold neutron (CN) flux and an analytical approach to calculate the UCN production from the simulated CN flux was given. A super-thermal source (UCN source) was modeled based on an arrangement of D{sub 2}O and solid D{sub 2} (sD{sub 2}). The D{sub 2}O was investigated as the neutron moderator, and sD{sub 2} as the converter. In order to determine the required parameters, a two-dimensional (2D) neutron balance equation written in Matlab was combined with the MCNPX simulation code. The 2D neutron-transport equation in cylindrical (? ? z) geometry was considered for 330 neutron energy groups in the sD{sub 2}. The 2D balance equation for UCN and CN was solved using simulated CN flux as boundary value. The UCN source dimensions were calculated for the development of the next UCN source. In the optimal condition, the UCN flux and the UCN production rate (averaged over the sD{sub 2} volume) equal to 6.79??10{sup 6} cm{sup ?2}s{sup ?1} and 2.20 10{sup 5} cm{sup ?3}s{sup ?1}, respectively.

Gheisari, R., E-mail: gheisari@pgu.ac.ir [Physics Department, Persian Gulf University, Bushehr 75169 (Iran, Islamic Republic of); Nuclear Energy Research Center, Persian Gulf University, Bushehr 75169 (Iran, Islamic Republic of); Firoozabadi, M. M.; Mohammadi, H. [Department of Physics, University of Birjand, Birjand 97175 (Iran, Islamic Republic of)] [Department of Physics, University of Birjand, Birjand 97175 (Iran, Islamic Republic of)

2014-01-15T23:59:59.000Z

223

Physics Analyses in the Design of the HFIR Cold Neutron Source  

SciTech Connect (OSTI)

Physics analyses have been performed to characterize the performance of the cold neutron source to be installed in the High Flux Isotope Reactor at the Oak Ridge National Laboratory in the near future. This paper provides a description of the physics models developed, and the resulting analyses that have been performed to support the design of the cold source. These analyses have provided important parametric performance information, such as cold neutron brightness down the beam tube and the various component heat loads, that have been used to develop the reference cold source concept.

Bucholz, J.A.

1999-09-27T23:59:59.000Z

224

Secondary Startup Neutron Sources as a Source of Tritium in a Pressurized Water Reactor (PWR) Reactor Coolant System (RCS)  

SciTech Connect (OSTI)

The hypothesis of this paper is that the Zircaloy clad fuel source is minimal and that secondary startup neutron sources are the significant contributors of the tritium in the RCS that was previously assigned to release from fuel. Currently there are large uncertainties in the attribution of tritium in a Pressurized Water Reactor (PWR) Reactor Coolant System (RCS). The measured amount of tritium in the coolant cannot be separated out empirically into its individual sources. Therefore, to quantify individual contributors, all sources of tritium in the RCS of a PWR must be understood theoretically and verified by the sum of the individual components equaling the measured values.

Shaver, Mark W.; Lanning, Donald D.

2010-02-01T23:59:59.000Z

225

Neutron production using a pyroelectric driven target coupled with a gated field ionization source  

SciTech Connect (OSTI)

A palm sized, portable neutron source would be useful for widespread implementation of detection systems for shielded, special nuclear material. We present progress towards the development of the components for an ultracompact neutron generator using a pulsed, meso-scale field ionization source, a deuterated (or tritiated) titanium target driven by a negative high voltage lithium tantalate crystal. Neutron production from integrated tests using an ion source with a single, biased tungsten tip and a 3 Multiplication-Sign 1 cm, vacuum insulated crystal with a plastic deuterated target are presented. Component testing of the ion source with a single tip produces up to 3 nA of current. Dielectric insulation of the lithium tantalate crystals appears to reduce flashover, which should improve the robustness. The field emission losses from a 3 cm diameter crystal with a plastic target and 6 cm diameter crystal with a metal target are compared.

Ellsworth, J. L.; Tang, V.; Falabella, S. [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550 (United States); Naranjo, B.; Putterman, S. [University of California Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90095 (United States)

2013-04-19T23:59:59.000Z

226

The Neutron Science TeraGrid Gateway, a TeraGrid Science Gateway to Support the Spallation Neutron Source  

SciTech Connect (OSTI)

The National Science Foundation's (NSF's) Extensible Terascale Facility (ETF), or TeraGrid [1] is entering its operational phase. An ETF science gateway effort is the Neutron Science TeraGrid Gateway (NSTG.) The Oak Ridge National Laboratory (ORNL) resource provider effort (ORNL-RP) during construction and now in operations is bridging a large scale experimental community and the TeraGrid as a large-scale national cyberinfrastructure. Of particular emphasis is collaboration with the Spallation Neutron Source (SNS) at ORNL. The U.S. Department of Energy's (DOE's) SNS [2] at ORNL will be commissioned in spring of 2006 as the world's brightest source of neutrons. Neutron science users can run experiments, generate datasets, perform data reduction, analysis, visualize results; collaborate with remotes users; and archive long term data in repositories with curation services. The ORNL-RP and the SNS data analysis group have spent 18 months developing and exploring user requirements, including the creation of prototypical services such as facility portal, data, and application execution services. We describe results from these efforts and discuss implications for science gateway creation. Finally, we show incorporation into implementation planning for the NSTG and SNS architectures. The plan is for a primarily portal-based user interaction supported by a service oriented architecture for functional implementation.

Cobb, John W [ORNL; Geist, Al [ORNL; Kohl, James Arthur [ORNL; Miller, Stephen D [ORNL; Peterson, Peter F [ORNL; Pike, Gregory [ORNL; Reuter, Michael A [ORNL; Swain, William [ORNL; Vazhkudai, Sudharshan S [ORNL; Vijayakumar, Nithya N [ORNL

2006-01-01T23:59:59.000Z

227

Terahertz Light Source and User Area at FACET  

SciTech Connect (OSTI)

FACET at SLAC provides high charge, high peak current, low emittance electron beam that is bunched at THz wavelength scale during its normal operation. A THz light source based coherent transition radiation (CTR) from this beam would potentially be the brightest short-pulse THz source ever constructed. Efforts have been put into building this photon source together with a user area, to provide a platform to utilize this unique THz radiation for novel nonlinear and ultrafast phenomena researches and experiments. Being a long-time underutilized portion of the electromagnetic spectrum, terahertz (100 GHz {approx} 10 THz) spectral range is experiencing a renaissance in recent years, with broad interests from chemical and biological imaging, material science, telecommunication, semiconductor and superconductor research, etc. Nevertheless, the paucity of THz sources especially strong THz radiation hinders both its commercial applications and nonlinear processes research. FACET - Facilities for Accelerator science and Experimental Test beams at SLAC - provides 23 GeV electron beam with peak currents of {approx} 20 kA that can be focused down to 100 {mu}m{sup 2} transversely. Such an intense electron beam, when compressed to sub-picosecond longitudinal bunch length, coherently radiates high intensity EM fields well within THz frequency range that are orders of magnitude stronger than those available from laboratory tabletop THz sources, which will enable a wide variety of THz related research opportunities. Together with a description of the FACET beamline and electron beam parameters, this paper will report FACET THz radiation generation via coherent transition radiation and calculated photon yield and power spectrum. A user table is being set up along the THz radiation extraction sites, and equipped with various signal diagnostics including THz power detector, Michelson interferometer, sample stages, and sets of motorized optical components. This setup will also be presented. Potential THz research areas including studies of magnetism, ferroelectric switching dynamics, semiconductor devices and chemical reaction controls have already been proposed for the FACET THz area.

Wu, Z.; Li, S.Z.; Litos, M.; Fisher, A.D.; Hogan, M.J.; /SLAC

2011-11-08T23:59:59.000Z

228

A D-T neutron source for fusion materials and technology testing  

SciTech Connect (OSTI)

This report describes a conceptual design of a high-fluence source of 14 MeV D-T neutrons for accelerated testing of materials. The design goal of 10 MW/m/sup 2/ year corresponding to 100 displacements per atom per year is taken to be sufficient for end-of-life tests of candidate materials for a fusion reactor. Such a neutron source would meet a need in the program to develop commercial fusion power that is not yet addressed. In our evaluation, a fusion-based source is preferred for this application over non-fusion, accelerator-type sources such as FMIT because, first, a relevant 14 MeV D-T neutron spectrum is obtained. Second, a fusion source will better simulate the reactor environment where materials can be subjected to high thermal loads, energetic particle irradiation, high mechanical stresses, intense magnetic fields and high magnetic field gradients as well as a 14 MeV neutron flux of several MW/m/sup 2/. Although the actual reactor environment can be realized only in a reactor, a fusion-based neutron source can give valuable design information of synergistic effects in this complex environment. The proposed small volume, high-fluence source would complement the capabilities of a facility such as ITER, which addresses toroidal fusion component development. For our source, the volume of reacting plasma and the fusion power have been minimized, while maintaining an intense neutron flux. As a consequence, tritium consumption is modest, and the amount of tritium required is readily available.

Coensgen, F.H.; Casper, T.A.; Correll, D.L.; Damm, C.C.; Futch, A.H.; Molvik, A.W.; Bulmer, R.H.

1987-08-01T23:59:59.000Z

229

Ultracold neutron source at the PULSTAR reactor: Engineering design and cryogenic testing  

Science Journals Connector (OSTI)

Abstract Construction is completed and commissioning is in progress for an ultracold neutron (UCN) source at the PULSTAR reactor on the campus of North Carolina State University. The source utilizes two stages of neutron moderation, one in heavy water at room temperature and the other in solid methane at ~ 40 K , followed by a converter stage, solid deuterium at 5K, that allows a single down scattering of cold neutrons to provide UCN. The UCN source rolls into the thermal column enclosure of the PULSTAR reactor, where neutrons will be delivered from a bare face of the reactor core by streaming through a graphite-lined assembly. The source infrastructure, i.e., graphite-lined assembly, heavy-water system, gas handling system, and helium liquefier cooling system, has been tested and all systems operate as predicted. The research program being considered for the PULSTAR UCN source includes the physics of UCN production, fundamental particle physics, and material surface studies of nanolayers containing hydrogen. In the present paper we report details of the engineering and cryogenic design of the facility as well as results of critical commissioning tests without neutrons.

E. Korobkina; G. Medlin; B. Wehring; A.I. Hawari; P.R. Huffman; A.R. Young; B. Beaumont; G. Palmquist

2014-01-01T23:59:59.000Z

230

Conceptual design of a reversed-field pinch fusion neutron source  

SciTech Connect (OSTI)

The conceptual design of an ohmically-heated, reversed-field pinch (RFP) operating with a 5-MWm/sup 2/ steady-state DT fusion neutron wall loading while generating /approximately/100-MW total fusion power is presented. These results are also useful in projecting the development of an economic source of DT neutrons for large-volume (/approximately/10 m/sup 3/) fusion nuclear testing. 6 refs., 4 figs., 5 tabs.

Bathke, C.G.; Krakowski, R.A.; Manzanares, R.G.; Miller, R.L.; Werley, K.A.

1988-01-01T23:59:59.000Z

231

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

SciTech Connect (OSTI)

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

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

2002-12-30T23:59:59.000Z

232

Compact D-D Neutron Source-Driven Subcritical Multiplier and Beam-Shaping Assembly for Boron Neutron Capture Therapy  

SciTech Connect (OSTI)

This work assesses the feasibility of using a small, safe, and inexpensive keff 0.98 subcritical fission assembly [subcritical neutron multiplier (SCM)] to amplify the treatment neutron beam intensity attainable from a compact deuterium-deuterium (D-D) fusion neutron source delivering [approximately]1012 n/s. The objective is to reduce the treatment time for deep-seated brain tumors to [approximately]1 h. The paper describes the optimal SCM design and two optimal beam-shaping assemblies (BSAs) - one designed to maximize the dose rate and the other designed to maximize the total dose that can be delivered to a deep-seated tumor. The neutron beam intensity amplification achieved with the optimized SCM and BSA results in an increase in the treatment dose rate by a factor of 18: from 0.56 Gy/h without the SCM to 10.1 Gy/h. The entire SCM is encased in an aluminum structure. The total amount of 20% enriched uranium required for the SCM is 8.5 kg, and the cost (not including fabrication) is estimated to be less than $60,000. The SCM power level is estimated at 400 W when driven by a 1012 n/s D-D neutron source. This translates into consumption of only [approximately]0.6% of the initially loaded 235U atoms during 50 years of continuous operation and implies that the SCM could operate continuously for the entire lifetime of the facility without refueling. Cooling the SCM does not pose a challenge; it may be accomplished by natural circulation as the maximum heat flux is only 0.034 W/cm2.

Francesco Ganda; Jasmina Vujic; Ehud Greenspan; Ka-Ngo Leung

2010-12-01T23:59:59.000Z

233

National Synchrotron Light Source A View of Brookhaven  

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

managed for the U.S. Department of Energy managed for the U.S. Department of Energy by Brookhaven Science Associates, a company founded by Stony Brook University and Battelle managed for the U.S. Department of Energy by Brookhaven Science Associates, a company founded by Stony Brook University and Battelle National Synchrotron Light Source A View of Brookhaven Brookhaven National Laboratory is a multipurpose re- search laboratory funded by the U.S. Department of En- ergy. Located on a 5,300-acre site on Long Island, New York, the Laboratory operates large-scale facilities for studies in physics, chemistry, biology, medicine, applied science, and advanced technology. Brookhaven's 2,600 scientists, engineers, and support staff are joined each year by more than 5,000 visiting research- ers from around the world.

234

Workshop on scientific applications of short wavelength coherent light sources  

SciTech Connect (OSTI)

This report contains paper on the following topics: A 2 to 4nm High Power FEL On the SLAC Linac; Atomic Physics with an X-ray Laser; High Resolution, Three Dimensional Soft X-ray Imaging; The Role of X-ray Induced Damage in Biological Micro-imaging; Prospects for X-ray Microscopy in Biology; Femtosecond Optical Pulses ; Research in Chemical Physics Surface Science, and Materials Science, with a Linear Accelerator Coherent Light Source; Application of 10 GeV Electron Driven X-ray Laser in Gamma-ray Laser Research; Non-Linear Optics, Fluorescence, Spectromicroscopy, Stimulated Desorption: We Need LCLS' Brightness and Time Scale; Application of High Intensity X-rays to Materials Synthesis and Processing; LCLS Optics: Selected Technological Issues and Scientific Opportunities; Possible Applications of an FEL for Materials Studies in the 60 eV to 200 eV Spectral Region.

Spicer, W.; Arthur, J.; Winick, H.

1993-02-01T23:59:59.000Z

235

Workshop on scientific applications of short wavelength coherent light sources  

SciTech Connect (OSTI)

This report contains paper on the following topics: A 2 to 4nm High Power FEL On the SLAC Linac; Atomic Physics with an X-ray Laser; High Resolution, Three Dimensional Soft X-ray Imaging; The Role of X-ray Induced Damage in Biological Micro-imaging; Prospects for X-ray Microscopy in Biology; Femtosecond Optical Pulses?; Research in Chemical Physics Surface Science, and Materials Science, with a Linear Accelerator Coherent Light Source; Application of 10 GeV Electron Driven X-ray Laser in Gamma-ray Laser Research; Non-Linear Optics, Fluorescence, Spectromicroscopy, Stimulated Desorption: We Need LCLS` Brightness and Time Scale; Application of High Intensity X-rays to Materials Synthesis and Processing; LCLS Optics: Selected Technological Issues and Scientific Opportunities; Possible Applications of an FEL for Materials Studies in the 60 eV to 200 eV Spectral Region.

Spicer, W.; Arthur, J.; Winick, H.

1993-02-01T23:59:59.000Z

236

Linac Coherent Light Source Undulator RF BPM System  

SciTech Connect (OSTI)

The Linac Coherent Light Source (LCLS) will be the world's first x-ray free-electron laser (FEL) when it becomes operational in 2009. The LCLS is currently in the construction phase. The beam position monitor (BPM) system planned for the LCLS undulator will incorporate a high-resolution X-band cavity BPM system described in this paper. The BPM system will provide high-resolution measurements of the electron beam trajectory on a pulse-to-pulse basis and over many shots. The X-band cavity BPM size, simple fabrication, and high resolution make it an ideal choice for LCLS beam position detection. We will discuss the system specifications, design, and prototype test results.

Lill, R.M.; Morrison, L.H.; Waldschmidt, G.J.; Walters, D.R.; /Argonne; Johnson, R.; Li, Z.; Smith, S.; Straumann, T.; /SLAC

2007-04-17T23:59:59.000Z

237

Compact light source performance in recessed type luminaires  

SciTech Connect (OSTI)

Photometric comparisons were made with an indoor, recessed, type luminaire using incandescent, high intensity discharge and compact fluorescent lamps. The test results show substantial performance advantages, as expected, for the discharge light sources where the efficacy gains can be in the order for 400% even when including the ballast losses associated with the discharge lamps. The candlepower distribution patterns emerging from these luminaries are also different from those associated with the baseline incandescent lamps, and which are in some ways, even more desirable from a uniformity of illuminance perspective. A section on fluorescent lamp starting is also included which describes a system having excellent starting characteristics in terms of electrode starting temperature (RH/RC technique), proper operating frequency to minimize unwanted IR interactions, and satisfactory current crest factor values to help insure life performance.

Hammer, E.E.

1998-11-01T23:59:59.000Z

238

Shedding Light on Protein Drug Interactions | Advanced Photon Source  

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

Science Highlights Archives: 2013 | 2012 | 2011 | 2010 Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Shedding Light on Protein Drug Interactions JANUARY 23, 2008 Bookmark and Share In this e-coli cell, the proteins (shown in blue) crowd around ribosomes (purple). These regions have a high concentration of protein, typically greater than 30 percent, which limits the ensemble of states into which the proteins can bend themselves. Download hi-res image.) Proteins, the biological molecules that are involved in virtually every action of every organism, may themselves move in surprising ways, according to a recent study carried out at the Biophysics Collaborative Access Team x-ray beamline 18-ID at the Advanced Photon Source, a national user

239

National Synchrotron Light Source guidelines for the conduct of operations  

SciTech Connect (OSTI)

To improve the quality and uniformity of operations at the Department of Energy`s facilities, the DOE issued Order 5480.19 ``Conduct of Operations Requirements at DOE facilities.`` This order recognizes that the success of a facilities mission critically depends upon a high level of performance by its personnel and equipment. This performance can be severely impaired if the facility`s Conduct of Operations pays inadequate attention to issues of organization, safety, health, and the environment. These guidelines are Brookhaven National Laboratory`s and the National Synchrotron Light Source`s acknowledgement of the principles of Conduct of Operations and the response to DOE Order 5480.19. These guidelines cover the following areas: (1) operations organization and administration; (2) shift routines and operating practices; (3) control area activities; (4) communications; (5) control of on-shift training; (6) investigation of abnormal events; (7) notifications; (8) control of equipment and system studies; (9) lockouts and tagouts; (10) independent verification; (11) log-keeping; (12) operations turnover; (13) operations aspects of facility process control (14) required reading; (15) timely orders to operators; (16) operations procedures; (17) operator aid posting; and (18) equipment sizing and labeling.

Buckley, M. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source

1998-01-01T23:59:59.000Z

240

Electron-beam-driven nanoscale metamaterial light sources  

Science Journals Connector (OSTI)

We show experimentally that beams of free electrons can induce light emission from nanoscale planar photonic metamaterials. Wavelengths of emitted light are determined by both the...

Adamo, Giorgio; Ou, Jun-Yu; MacDonald, Kevin; De Angelis, Francesco; Di Fabrizio, Enzo; Zheludev, Nikolay

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


241

Active beam position stabilization of pulsed lasers for long-distance ion profile diagnostics at the Spallation Neutron Source (SNS)  

SciTech Connect (OSTI)

A high peak-power Q-switched laser has been used to monitor the ion beam profiles in the superconducting linac at the Spallation Neutron Source (SNS). The laser beam suffers from position drift due to movement, vibration, or thermal effects on the optical components in the 250-meter long laser beam transport line. We have designed, bench-tested, and implemented a beam position stabilization system by using an Ethernet CMOS camera, computer image processing and analysis, and a piezo-driven mirror platform. The system can respond at frequencies up to 30 Hz with a high position detection accuracy. With the beam stabilization system, we have achieved a laser beam pointing stability within a range of 2 rad (horizontal) to 4 rad (vertical), corresponding to beam drifts of only 0.5 mm 1 mm at the furthest measurement station located 250 meters away from the light source.

Hardin, Robert A [ORNL; Liu, Yun [ORNL; Long, Cary D [ORNL; Aleksandrov, Alexander V [ORNL; Blokland, Willem [ORNL

2011-01-01T23:59:59.000Z

242

A dual neutron/gamma source for the Fissmat Inspection for Nuclear Detection (FIND) system.  

SciTech Connect (OSTI)

Shielded special nuclear material (SNM) is very difficult to detect and new technologies are needed to clear alarms and verify the presence of SNM. High-energy photons and neutrons can be used to actively interrogate for heavily shielded SNM, such as highly enriched uranium (HEU), since neutrons can penetrate gamma-ray shielding and gamma-rays can penetrate neutron shielding. Both source particles then induce unique detectable signals from fission. In this LDRD, we explored a new type of interrogation source that uses low-energy proton- or deuteron-induced nuclear reactions to generate high fluxes of mono-energetic gammas or neutrons. Accelerator-based experiments, computational studies, and prototype source tests were performed to obtain a better understanding of (1) the flux requirements, (2) fission-induced signals, background, and interferences, and (3) operational performance of the source. The results of this research led to the development and testing of an axial-type gamma tube source and the design/construction of a high power coaxial-type gamma generator based on the {sup 11}B(p,{gamma}){sup 12}C nuclear reaction.

Doyle, Barney Lee (Sandia National Laboratories, Albuquerque, NM); King, Michael; Rossi, Paolo (Sandia National Laboratories, Albuquerque, NM); McDaniel, Floyd Del (Sandia National Laboratories, Albuquerque, NM); Morse, Daniel Henry; Antolak, Arlyn J.; Provencio, Paula Polyak (Sandia National Laboratories, Albuquerque, NM); Raber, Thomas N.

2008-12-01T23:59:59.000Z

243

SOURCES: a code for calculating (,n), spontaneous fission, and delayed neutron sources and spectra  

Science Journals Connector (OSTI)

......available nuclides are isotopes of Po, Rn, Ra, Th...as well as six Pu isotopes and one Be isotope were present. Reasonable...including lithium, 9Be, boron, carbon, oxygen...23. Stewart, L. Determination of the neutron spectrum......

W. B. Wilson; R. T. Perry; W. S. Charlton; T. A. Parish; E. F. Shores

2005-12-20T23:59:59.000Z

244

A 14-MeV beam-plasma neutron source for materials testing  

SciTech Connect (OSTI)

The design and performance of 14-MeV beam-plasma neutron sources for accelerated testing of fusion reactor materials are described. Continuous production of 14-MeV neutron fluxes in the range of 5 to 10 MW/m{sup 2} at the plasma surface are produced by D-T reactions in a two-component plasma. In the present designs, 14-MeV neutrons result from collisions of energetic deuterium ions created by transverse injection of 150-keV deuterium atoms on a fully ionized tritium target plasma. The beam energy, which deposited at the center of the tritium column, is transferred to the warm plasma by electron drag, which flows axially to the end regions. Neutral gas at high pressure absorbs the energy in the tritium plasma and transfers the heat to the walls of the vacuum vessel. The plasma parameters of the neutron source, in dimensionless units, have been achieved in the 2XIIB high-{beta} plasma. The larger magnetic field of the present design permits scaling to the higher energy and density of the neutron source design. In the extrapolation, care has been taken to preserve the scaling and plasma attributes that contributed to equilibrium, magnetohydrodynamic (MHD) stability, and microstability in 2XIIB. The performance and scaling characteristics are described for several designs chosen to enhance the thermal isolation of the two-component plasmas. 11 refs., 3 figs., 3 tabs.

Futch, A.H.; Coensgen, F.H.; Damm, C.C.; Molvik, A.W.

1989-01-01T23:59:59.000Z

245

UNIVERSITY OF COLORADO BOULDER Light from the Sun is the largest source of energy  

E-Print Network [OSTI]

's atmosphere. The Solar Influences group at LASP studies the light from the Sun and how it interacts · How solar light affects Earth's climate and atmosphere · The ways solar light affects space weatherUNIVERSITY OF COLORADO BOULDER Light from the Sun is the largest source of energy for Earth

Mojzsis, Stephen J.

246

The Development of the Linac Coherent Light Source RF Gun  

SciTech Connect (OSTI)

The Linac Coherent Light Source (LCLS) is the first x-ray laser user facility based upon a free electron laser (FEL) requiring extraordinary beam quality to saturate at 1.5 angstroms within a 100 meter undulator.[1] This new type of light source is using the last kilometer of the three kilometer linac at SLAC to accelerate the beam to an energy as high as 13.6 GeV and required a new electron gun and injector to produce a very bright beam for acceleration. At the outset of the project it was recognized that existing RF guns had the potential to produce the desired beam but none had demonstrated it. Therefore a new RF gun or at least the modification of an existing gun was necessary. The parameters listed in Table 1 illustrate the unique characteristics of LCLS which drive the requirements for the electron gun as given in Table 2. The gun beam quality needs to accommodate emittance growth as the beam is travels through approximately one kilometer of linac and two bunch compressors before reaching the undulator. These beam requirements were demonstrated during the recent commissioning runs of the LCLS injector and linac [2] due to the successful design, fabrication, testing and operation of the LCLS gun. The goal of this paper is to relate the technical background of how the gun was able to achieve and in some cases exceed these requirements by understanding and correcting the deficiencies of the prototype s-band RF photocathode gun, the BNL/SLAC/UCLA Gun III. This paper begins with a brief history and technical description of Gun III and the Gun Test Facility (GTF) at SLAC, and studies of the gun's RF and emittance compensation solenoid. The work at the GTF identified the gun and solenoid deficiencies, and helped to define the specifications for the LCLS gun. Section 1.1.5 describes the modeling used to compute and correct the gun RF fields and Section 1.1.6 describes the use of these fields in the electron beam simulations. The magnetic design and measurements of the emittance compensation solenoid are discussed in Section 1.1.7. The novel feature of the LCLS solenoid is the embedded quadrupole correctors. The thermo-mechanical engineering of the LCLS gun is discussed in Section 1.1.8, and the cold and hot RF tests are described in Section 1.1.9. The results of this work are summarized and concluding remarks are given in Section 1.1.10.

Dowell, David H.; Jongewaard, Erik; Lewandowski, James; Limborg-Deprey, Cecile; Li, Zenghai; Schmerge, John; Vlieks, Arnold; Wang, Juwen; Xiao, Liling; /SLAC

2008-09-24T23:59:59.000Z

247

Experiment Automation with a Robot Arm using the Liquids Reflectometer Instrument at the Spallation Neutron Source  

SciTech Connect (OSTI)

The Liquids Reflectometer instrument installed at the Spallation Neutron Source (SNS) enables observations of chemical kinetics, solid-state reactions and phase-transitions of thin film materials at both solid and liquid surfaces. Effective measurement of these behaviors requires each sample to be calibrated dynamically using the neutron beam and the data acquisition system in a feedback loop. Since the SNS is an intense neutron source, the time needed to perform the measurement can be the same as the alignment process, leading to a labor-intensive operation that is exhausting to users. An update to the instrument control system, completed in March 2013, implemented the key features of automated sample alignment and robot-driven sample management, allowing for unattended operation over extended periods, lasting as long as 20 hours. We present a case study of the effort, detailing the mechanical, electrical and software modifications that were made as well as the lessons learned during the integration, verification and testing process.

Zolnierczuk, Piotr A [ORNL; Vacaliuc, Bogdan [ORNL; Sundaram, Madhan [ORNL; Parizzi, Andre A [ORNL; Halbert, Candice E [ORNL; Hoffmann, Michael C [ORNL; Greene, Gayle C [ORNL; Browning, Jim [ORNL; Ankner, John Francis [ORNL

2013-01-01T23:59:59.000Z

248

Neutron-capture elements in the very metal-poor star HD88609: another st ar with excesses of light neutron-capture elements  

E-Print Network [OSTI]

We obtained a high resolution, high signal-to-noise UV-blue spectrum of the extremely metal-poor red giant HD88609 to determine the abundances of heavy elements. Nineteen neutron-capture elements are detected in the spectrum. Our analysis revealed that this object has large excesses of light neutron-capture elements while heavy neutron-capture elements are deficient. The abundance pattern shows a continuously decreasing trend, as a function of atomic number, from Sr to Yb, which is quite different from those in stars with excesses of r-process elements. Such an abundance pattern is very similar to that of HD122563 that was studied by our previous work. The results indicate that the abundance pattern found in the two stars could represent the pattern produced by the nucleosynthesis process that provided light neutron-capture elements in the very early Galaxy.

Satoshi Honda; Wako Aoki; Yuhri Ishimaru; Shinya Wanajo

2007-05-27T23:59:59.000Z

249

Cross-Fertilization between Spallation Neutron Source and Third Generation Synchrotron Radiation Detectors  

SciTech Connect (OSTI)

Suffering presently from relatively low source strengths compared to synchrotron radiation investigations, neutron scattering methods will greatly benefit from the increase of instantaneous flux attained at the next generation of pulsed spallation neutron sources. In particular at ESS, the strongest projected source, the counting rate load on the detectors will rise by factors of up to 50-150 in comparison with present generic instruments. For these sources the detector requirements overlap partly with those for modern synchrotron radiation detectors as far as counting rate capability and two-dimensional position resolution are concerned. In this paper, examples of the current and forthcoming detector development, comprising e.g. novel solutions for low-pressure micro-strip gas chamber detectors, for silicon micro-strip detectors and for the related front-end ASICs and data acquisition (DAQ) systems, are summarized, which will be of interest for detection of synchrotron radiation as well.

Gebauer, B.; Schulz, Ch.; Alimov, S.S.; Wilpert, Th. [Hahn-Meitner-Instiut Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Levchanovsky, F.V. [Hahn-Meitner-Instiut Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Frank Laboratory of Neutron Physics, Joint Institute of Nuclear Research, 141980 Dubna (Russian Federation); Litvinenko, E.I.; Nikiforov, A.S. [Frank Laboratory of Neutron Physics, Joint Institute of Nuclear Research, 141980 Dubna (Russian Federation)

2004-05-12T23:59:59.000Z

250

OPTIONS FOR A STEADY-STATE COMPACT FUSION NEUTRON SOURCE M.P. Gryaznevich1  

E-Print Network [OSTI]

in the Fusion for Neutrons (F4N) approach. This is because the nuclear fusion reaction produces an abundance (power output over power input) to be viable as a power source, fusion still has a valuable role-fission process can provide a large gain over the input energy and yield sufficient heat output for economical

251

GDT-based neutron source with multiple-mirror end plugs  

SciTech Connect (OSTI)

We present a new linear trap to be built at the Budker Institute. It combines gasdynamictype central cell with sloshing ions for beam fusion and the multiple-mirror end plugs for improved axial confinement. Thus it is designed as an efficient neutron source and a testbed for future development of mirror-based fusion reactors.

Beklemishev, A.; Anikeev, A.; Burdakov, A.; Ivanov, A.; Ivanov, I.; Postupaev, V.; Sinitsky, S. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)

2012-06-19T23:59:59.000Z

252

The Corrosion of Materials in Spallation Neutron Sources R. Scott Lillard, Darryl P. Butt  

E-Print Network [OSTI]

1 The Corrosion of Materials in Spallation Neutron Sources R. Scott Lillard, Darryl P. Butt Materials Corrosion and Environmental Effects Lab Materials Science and Technology Division, MST-6 Los current efforts to measure the real-time corrosion rates of Alloy 718 (718) during 800 MeV proton

253

Summary of mirror experiments relevant to beam-plasma neutron source  

SciTech Connect (OSTI)

A promising design for a deuterium-tritium (DT) neutron source is based on the injection of neutral beams into a dense, warm plasma column. Its purpose is to test materials for possible use in fusion reactors. A series of designs have evolved, from a 4-T version to an 8-T version. Intense fluxes of 5--10 MW/m/sup 2/ is achieved at the plasma surface, sufficient to complete end-of-life tests in one to two years. In this report, we review data from earlier mirror experiments that are relevant to such neutron sources. Most of these data are from 2XIIB, which was the only facility to ever inject 5 MW of neutral beams into a single mirror call. The major physics issues for a beam-plasma neutron source are magnetohydrodynamic (MHD) equilibrium and stability, microstability, startup, cold-ion fueling of the midplane to allow two-component reactions, and operation in the Spitzer conduction regime, where the power is removed to the ends by an axial gradient in the electron temperature T/sub e/. We show in this report that the conditions required for a neutron source have now been demonstrated in experiments. 20 refs., 15 figs., 3 tabs.

Molvik, A.W.

1988-10-18T23:59:59.000Z

254

Coherent Scattering Investigations at the Spallation Neutron Source: a Snowmass White Paper  

SciTech Connect (OSTI)

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, Tennessee, provides an intense flux of neutrinos in the few tens-of-MeV range, with a sharply-pulsed timing structure that is beneficial for background rejection. In this white paper, we describe how the SNS source can be used for a measurement of coherent elastic neutrino-nucleus scattering (CENNS), and the physics reach of different phases of such an experimental program (CSI: Coherent Scattering Investigations at the SNS).

Akimov, D. [Moscow Engineering Physics Institute (MEPhI), Russia] Moscow Engineering Physics Institute (MEPhI), Russia; Bernstein, A. [Lawrence Livermore National Laboratory (LLNL)] Lawrence Livermore National Laboratory (LLNL); BarbeauP., [Duke University; Barton, P. J. [Lawrence Berkeley National Laboratory (LBNL)] Lawrence Berkeley National Laboratory (LBNL); Bolozdynya, A. [Moscow Engineering Physics Institute (MEPhI), Russia] Moscow Engineering Physics Institute (MEPhI), Russia; Cabrera-Palmer, B. [Sandia National Laboratories (SNL)] Sandia National Laboratories (SNL); Cavanna, F. [Yale University] Yale University; Cianciolo, Vince [ORNL] ORNL; Collar, J. [University of Chicago, Enrico Fermi Institute] University of Chicago, Enrico Fermi Institute; Cooper, R. J. [Indiana University] Indiana University; Dean, D. J. [Oak Ridge National Laboratory (ORNL)] Oak Ridge National Laboratory (ORNL); Efremenko, Yuri [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL)] University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Etenko, A. [Moscow Engineering Physics Institute (MEPhI), Russia] Moscow Engineering Physics Institute (MEPhI), Russia; Fields, N. [University of Chicago, Enrico Fermi Institute] University of Chicago, Enrico Fermi Institute; Foxe, M. [Pennsylvania State University, University Park, PA] Pennsylvania State University, University Park, PA; Figueroa-Feliciano, E. [Massachusetts Institute of Technology (MIT)] Massachusetts Institute of Technology (MIT); Fomin, N. [University of Tennessee, Knoxville (UTK)] University of Tennessee, Knoxville (UTK); Gallmeier, F. [Oak Ridge National Laboratory (ORNL)] Oak Ridge National Laboratory (ORNL); Garishvili, I. [University of Tennessee, Knoxville (UTK)] University of Tennessee, Knoxville (UTK); Gerling, M. [Sandia National Laboratories (SNL)] Sandia National Laboratories (SNL); Green, M. [University of North Carolina, Chapel Hill] University of North Carolina, Chapel Hill; Greene, Geoffrey [University of Tennessee, Knoxville (UTK)] University of Tennessee, Knoxville (UTK); Hatzikoutelis, A. [University of Tennessee, Knoxville (UTK)] University of Tennessee, Knoxville (UTK); Henning, Reyco [University of North Carolina, Chapel Hill] University of North Carolina, Chapel Hill; Hix, R. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL)] University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Hogan, D. [University of California-Berkeley] University of California-Berkeley; Hornback, D. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL)] University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Jovanovic, I. [Pennsylvania State University, University Park, PA] Pennsylvania State University, University Park, PA; Hossbach, T. [Pacific Northwest National Laboratory (PNNL)] Pacific Northwest National Laboratory (PNNL); Iverson, Erik B [ORNL] ORNL; Klein, S. R. [Lawrence Berkeley National Laboratory (LBNL)] Lawrence Berkeley National Laboratory (LBNL); Khromov, A. [Moscow Engineering Physics Institute (MEPhI), Russia] Moscow Engineering Physics Institute (MEPhI), Russia; Link, J. [Virginia Polytechnic Institute and State University] Virginia Polytechnic Institute and State University; Louis, W. [Los Alamos National Laboratory (LANL)] Los Alamos National Laboratory (LANL); Lu, W. [Oak Ridge National Laboratory (ORNL)] Oak Ridge National Laboratory (ORNL); Mauger, C. [Los Alamos National Laboratory (LANL)] Los Alamos National Laboratory (LANL); Marleau, P. [Sandia National Laboratories (SNL)] Sandia National Laboratories (SNL); Markoff, D. [North Carolina Central University, Durham] North Carolina Central University, Durham; Martin, R. D. [University of South Dakota] University of South Dakota; Mueller, Paul Edward [ORNL] ORNL; Newby, J. [Oak Ridge National Laboratory (ORNL)] Oak Ridge National Laboratory (ORNL); Orrell, John L. [Pacific Northwest National Laboratory (PNNL)] Pacific Northwest National Laboratory (PNNL); O'Shaughnessy, C. [University of North Carolina, Chapel Hill] University of North Carolina, Chapel Hill

2013-01-01T23:59:59.000Z

255

Single-layer mirrors for advanced research light sources  

SciTech Connect (OSTI)

X-ray mirrors are needed for beam guidance, beam alignment and monochromatisation at third-generation synchrotron light sources (PETRA III) and forthcoming Free-Electron Lasers (LCLS, European XFEL). Amorphous carbon coatings are currently used as total reflection mirrors at FLASH to guide the photon beam to the various beamlines. These coatings were prepared by means of magnetron sputtering. The new GKSS sputtering facility for the deposition of single and multilayer mirrors with a length of up to 1500 mm and a width of up to 120 mm is in operation. In this contribution we present the results of this new deposition system. A major advantage is that it is now possible to prepare one, two or more mirrors with similar properties over the whole deposition length. The mirror properties were investigated by means of X-ray reflectometry and interference microscopy. The performance of the mirrors is analyzed, considering X-ray reflectivity, film thickness and surface roughness. The uniformity of these properties over the whole deposition length of 1500 mm is demonstrated. The results obtained will be discussed and compared with former results.

Stoermer, M.; Horstmann, C. [GKSS Research Centre Geesthacht GmbH, Institute of Materials Research, Max-Planck-Str. 1, D-21502 Geesthacht (Germany); Siewert, F. [Helmholtz Zentrum Berlin / BESSY-II, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Scholze, F.; Krumrey, M. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin (Germany); Hertlein, F.; Matiaske, M.; Wiesmann, J. [Incoatec GmbH, Max-Planck-Str. 2, D-21502 Geesthacht (Germany); Gaudin, J. [European XFEL, DESY, 22603 Hamburg (Germany)

2010-06-23T23:59:59.000Z

256

Beam-based Feedback for the Linac Coherent Light Source  

SciTech Connect (OSTI)

Beam-based feedback control loops are required by the Linac Coherent Light Source (LCLS) program in order to provide fast, single-pulse stabilization of beam parameters. Eight transverse feedback loops, a 6 x 6 longitudinal feedback loop, and a loop to maintain the electron bunch charge were successfully prototyped in MATLAB for the LCLS, and have been maintaining stability of the LCLS electron beam at beam rates up to 30Hz. In the final commissioning phase of LCLS the beam will be operating at up to 120Hz. In order to run the feedback loops at beam rate, the feedback loops will be implemented in EPICS IOCs with a dedicated ethernet multi-cast network. This paper will discuss the design of the beam-based Fast Feedback System for LCLS. Topics include MATLAB feedback prototyping, algorithm for 120Hz feedback, network design for fast data transport, actuator and sensor design for single-pulse control and sensor readback, and feedback configuration and runtime control.

Fairley, D.; Allison, S.; Chevtsov, S.; Chu, P.; Decker, F.J.; Emma, P.; Frisch, J.; Himel, T.; Kim, K.; Krejcik, P.; Loos, H.; Lahey, T.; Natampalli, P.; Peng, S.; Rogind, D.; Shoaee, H.; Straumann, T.; Williams, E.; White, G.; Wu, J.; Zelazney, M.; /SLAC

2010-02-11T23:59:59.000Z

257

Vacuum system for the LBL advanced light source (ALS)  

SciTech Connect (OSTI)

A 1.5 to 1.9 GeV synchrotron light source is being built at LBL. The vacuum system is designed to permit all synchrotron photons on the median plane to escape the electron channel and go into an antechamber through a 10 mm high slot. This slot offers effective RF isolation between the electron duct and the antechamber. All unused synchrotron photons within a few mrad of the median plane will be stopped by 96 nearly horizontal absorbers located in the antechamber. The gas, generated by the photons hitting the absorbers, will be directed down to reactive titanium surfaces. Twelve 10 meter long vessels constitute the vacuum chambers for all the lattice magnets. Each chamber will be machined from two thick plates of 5083-H321 aluminum and welded at the perimeter. The nominal wall thickness of the vacuum chamber is 40 mm, which makes it possible to machine a flange into the chamber without the use of welding. 5 refs., 5 figs.

Kennedy, K.

1988-05-01T23:59:59.000Z

258

Final Report, Photocathodes for High Repetition Rate Light Sources  

SciTech Connect (OSTI)

This proposal brought together teams at Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL) and Stony Brook University (SBU) to study photocathodes for high repetition rate light sources such as Free Electron Lasers (FEL) and Energy Recovery Linacs (ERL). The work done under this grant comprises a comprehensive program on critical aspects of the production of the electron beams needed for future user facilities. Our program pioneered in situ and in operando diagnostics for alkali antimonide growth. The focus is on development of photocathodes for high repetition rate Free Electron Lasers (FELs) and Energy Recovery Linacs (ERLs), including testing SRF photoguns, both normal-conducting and superconducting. Teams from BNL, LBNL and Stony Brook University (SBU) led this research, and coordinated their work over a range of topics. The work leveraged a robust infrastructure of existing facilities and the support was used for carrying out the research at these facilities. The program concentrated in three areas: a) Physics and chemistry of alkali-antimonide cathodes b) Development and testing of a diamond amplifier for photocathodes c) Tests of both cathodes in superconducting RF photoguns and copper RF photoguns

Ben-Zvi, Ilan [Stony Brook University

2014-04-20T23:59:59.000Z

259

Biological soft X-ray tomography on beamline 2.1 at the Advanced Light Source  

Science Journals Connector (OSTI)

Beamline 2.1, a transmission soft X-ray microscope at the Advanced Light Source of Lawrence Berkeley National Laboratory, is described.

Le Gros, M.A.

2014-10-01T23:59:59.000Z

260

Energy Recovered Light Source Technology at TJNAF | U.S. DOE...  

Office of Science (SC) Website

Energy Recovered Light Source Technology at TJNAF Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of Nuclear Science...

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


261

A proton?driven, intense, subcritical, fission neutron source for radioisotope production  

Science Journals Connector (OSTI)

99mTc the most frequently used radioisotope in nuclear medicine is distributed as 99Mo?99mTc generators. 99 Mo is a fission product of 235U. To replace the aging nuclear reactors used today for this production we propose to use a spallation neutron source with neutron multiplication by fission. A 150 MeV H? cyclotron can produce a 225 kW proton beam with 50% total system energy efficiency. The proton beam would hit a molten lead target surrounded by a water moderator and a graphite reflector producing around 0.96 primary neutron per proton. The primary spallation neutrons moderated would strike secondary targets containing a subcritical amount of 235U. The assembly would show a keff of 0.8 yielding a fivefold neutron multiplication. The thermal neutron flux at the targets location would be 2 1014 n/cm2.s resulting in a fission power of 500 to 750 kW. One such system could supply the world demand in 99 Mo as well as other radioisotopes. Preliminary indications show that the cost would be lower than the cost of a commercial 10 MW isotope production reactor. The cost of operation of disposal of radiowaste and of decommissioning should be significantly lower as well. Finally the non?critical nature of the system would make it more acceptable for the public than a nuclear reactor and should simplify the licensing process.

Yves Jongen

1995-01-01T23:59:59.000Z

262

The light-emitting diode (LED) is an fairly new kind of light source found currently in  

E-Print Network [OSTI]

this technology an ideal replacement for less efficient incandescent light sources, particularly in applications elevator lighting has the potential to achieve 25 percent greater efficiency than current incandescent ILLUMINATION LEVELS SIMILAR TO THOSE OF INCANDESCENT FIXTURES WHILE CUTTING ENERGY USE 45 PERCENT. ELEVATOR

263

Doppler effects of a light source on a metamaterial slab: a rigorous Green's function approach  

Science Journals Connector (OSTI)

We apply a (rigorous) Green's function theory to study the Doppler effects of a light source placed on top of a metamaterial slab. When the receiver is in motion with the source and...

Wang, Weihua; Huang, Xueqin; Zhou, Lei; Chan, C T

2008-01-01T23:59:59.000Z

264

Laser fusion neutron source employing compression with short pulse lasers  

DOE Patents [OSTI]

A method and system for achieving fusion is provided. The method includes providing laser source that generates a laser beam and a target that includes a capsule embedded in the target and filled with DT gas. The laser beam is directed at the target. The laser beam helps create an electron beam within the target. The electron beam heats the capsule, the DT gas, and the area surrounding the capsule. At a certain point equilibrium is reached. At the equilibrium point, the capsule implodes and generates enough pressure on the DT gas to ignite the DT gas and fuse the DT gas nuclei.

Sefcik, Joseph A; Wilks, Scott C

2013-11-05T23:59:59.000Z

265

Field ionization characteristics of an ion source array for neutron generators  

SciTech Connect (OSTI)

A new deuterium ion source is being developed to improve the performance of existing compact neutron generators. The ion source is a microfabricated array of metal tips with an integrated gate (i.e., grid) and produces deuterium ions by field ionizing (or field desorbing) a supply of deuterium gas. Deuterium field ion currents from arrays at source temperatures of 77 K and 293 K are studied. Ion currents from single etched-wire tips operating under the same conditions are used to help understand array results. I-F characteristics of the arrays were found to follow trends similar to those of the better understood single etched-wire tip results; however, the fields achieved by the arrays are limited by electrical breakdown of the structure. Neutron production by field ionization at 293 K was demonstrated for the first time from microfabricated array structures with integrated gates.

Bargsten Johnson, B.; Schwoebel, P. R. [University of New Mexico, Albuquerque, New Mexico 87131 (United States)] [University of New Mexico, Albuquerque, New Mexico 87131 (United States); Resnick, P. J. [Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States); Holland, C. E. [SRI International, Menlo Park, California 94025 (United States)] [SRI International, Menlo Park, California 94025 (United States); Hertz, K. L. [Sandia National Laboratories, Livermore, California 94551 (United States)] [Sandia National Laboratories, Livermore, California 94551 (United States); Chichester, D. L. [Idaho National Laboratory, Idaho Falls, Idaho 83415 (United States)] [Idaho National Laboratory, Idaho Falls, Idaho 83415 (United States)

2013-11-07T23:59:59.000Z

266

Neutron Radiography Facility in a Storage Pond of a Nuclear Power Station Equipped with Antimony-Beryllium Neutron Source  

Science Journals Connector (OSTI)

A neutron radiography facility is described, which has been ... . Some of the control elements contain the neutron absorbing material boron carbide, filled in tubes. Neutron radiography can be applied to detect a...

L. Greim; F. Borchers; M. Greim; G. W. Schumacher; H.-W. Schmitz

1987-01-01T23:59:59.000Z

267

Dielectric Wakefield Accelerator to drive the future FEL Light Source.  

SciTech Connect (OSTI)

X-ray free-electron lasers (FELs) are expensive instruments and a large part of the cost of the entire facility is driven by the accelerator. Using a high-energy gain dielectric wake-field accelerator (DWA) instead of the conventional accelerator may provide a significant cost saving and reduction of the facility size. In this article, we investigate using a collinear dielectric wakefield accelerator to provide a high repetition rate, high current, high energy beam to drive a future FEL x-ray light source. As an initial case study, a {approx}100 MV/m loaded gradient, 850 GHz quartz dielectric based 2-stage, wakefield accelerator is proposed to generate a main electron beam of 8 GeV, 50 pC/bunch, {approx}1.2 kA of peak current, 10 x 10 kHz (10 beamlines) in just 100 meters with the fill factor and beam loading considered. This scheme provides 10 parallel main beams with one 100 kHz drive beam. A drive-to-main beam efficiency {approx}38.5% can be achieved with an advanced transformer ratio enhancement technique. rf power dissipation in the structure is only 5 W/cm{sup 2} in the high repetition rate, high gradient operation mode, which is in the range of advanced water cooling capability. Details of study presented in the article include the overall layout, the transform ratio enhancement scheme used to increase the drive to main beam efficiency, main wakefield linac design, cooling of the structure, etc.

Jing, C.; Power, J.; Zholents, A. (Accelerator Systems Division (APS)); ( HEP); (LLC)

2011-04-20T23:59:59.000Z

268

High-Efficiency Nitride-Based Photonic Crystal Light Sources  

Broader source: Energy.gov [DOE]

The University of California Santa Barbara (UCSB) is maximizing the efficiency of a white LED by enhancing the external quantum efficiency using photonic crystals to extract light that would normally be confined in a conventional structure. Ultimate efficiency can only be achieved by looking at the internal structure of light. To do this, UCSB is focusing on maximizing the light extraction efficiency and total light output from light engines driven by Gallium Nitride (GaN)-based LEDs. The challenge is to engineer large overlap (interaction) between modes and photonic crystals. The project is focused on achieving high extraction efficiency in LEDs, controlled directionality of emitted light, integrated design of vertical device structure, and nanoscale patterning of lateral structure.

269

Polymer and small molecule based hybrid light source  

DOE Patents [OSTI]

An organic electroluminescent device, includes: a substrate; a hole-injecting electrode (anode) coated over the substrate; a hole injection layer coated over the anode; a hole transporting layer coated over the hole injection layer; a polymer based light emitting layer, coated over the hole transporting layer; a small molecule based light emitting layer, thermally evaporated over the polymer based light emitting layer; and an electron-injecting electrode (cathode) deposited over the electroluminescent polymer layer.

Choong, Vi-En (Carlsbad, CA); Choulis, Stelios (Nuremberg, DE); Krummacher, Benjamin Claus (Regensburg, DE); Mathai, Mathew (Monroeville, PA); So, Franky (Gainesville, FL)

2010-03-16T23:59:59.000Z

270

Relative performance properties of the ORNL Advanced Neutron Source Reactor with reduced enrichment fuels  

SciTech Connect (OSTI)

Three cores for the Advanced Neutron Source reactor, differing in size, enrichment, and uranium density in the fuel meat, have been analyzed. Performance properties of the reduced enrichment cores are compared with those of the HEU reference configuration. Core lifetime estimates suggest that none of these configurations will operate for the design goal of 17 days at 330 MW. With modes increases in fuel density and/or enrichment, however, the operating lifetimes of the HEU and MEU designs can be extended to the desired length. Achieving this lifetime with LEU fuel in any of the three studies cores, however, will require the successful development of denser fuels and/or structural materials with thermal neutron absorption cross sections substantially less than that of Al-6061. Relative to the HEU reference case, the peak thermal neutron flux in cores with reduced enrichment will be diminished by about 25--30%.

Bretscher, M.M.; Deen, J.R.; Hanan, N.A.; Matos, J.E.; Mo, S.C.; Pond, R.B.; Travelli, A.; Woodruff, W.L.

1994-12-31T23:59:59.000Z

271

Inelastic neutron scattering study of light-induced dynamics of a photosynthetic membrane system  

Science Journals Connector (OSTI)

Inelastic neutron scattering was employed to study photoeffects on the molecular dynamics of membranes of the photosynthetic bacterium Rhodopseudomonas viridis. The main photoactive parts of this biomolecular system are the chlorophyll molecules whose dynamics were found to be affected under illumination by visible light in a twofold manner. First, vibrational modes are excited at energies of 12(2) and 88(21)?cm?1. Second, a partial freezing of rotational modes is observed at energies of 1.2(3) and 2.9(5)?cm?1. These results are attributed to a possible coupling between molecular motions and particular mechanisms in the photosynthetic process.

A. Furrer and A. Stckli

2010-01-05T23:59:59.000Z

272

Micro optical fiber light source and sensor and method of fabrication thereof  

DOE Patents [OSTI]

This invention relates generally to the development of and a method of fabricating a micro optical fiber light source. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications. 4 figs.

Kopelman, R.; Tan, W.; Shi, Z.Y.

1994-11-01T23:59:59.000Z

273

Micro optical fiber light source and sensor and method of fabrication thereof  

DOE Patents [OSTI]

This invention relates generally to the development of and a method of fabricating a fiber optic micro-light source and sensor (50). An optical fiber micro-light source (50) is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors (22) in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material (60). This process allows significant control of the size of the micro light source (50). Furthermore, photo-chemically attaching an optically active material (60) enables the implementation of the micro-light source in a variety of sensor applications.

Kopelman, Raoul (Ann Arbor, MI); Tan, Weihong (Ames, IA); Shi, Zhong-You (Ann Arbor, MI)

1997-01-01T23:59:59.000Z

274

Micro optical fiber light source and sensor and method of fabrication thereof  

DOE Patents [OSTI]

This invention relates generally to the development of and a method of fabricating a micro optical fiber light source. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications.

Kopelman, Raoul (Ann Arbor, MI); Tan, Weihong (Ann Arbor, MI); Shi, Zhong-You (Ann Arbor, MI)

1994-01-01T23:59:59.000Z

275

Micro optical fiber light source and sensor and method of fabrication thereof  

DOE Patents [OSTI]

This invention relates generally to the development of and a method of fabricating a fiber optic micro-light source and sensor. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications. 10 figs.

Kopelman, R.; Tan, W.; Shi, Z.Y.

1997-05-06T23:59:59.000Z

276

Current-voltage model of LED light sources Szymon Bczkowski, Stig Munk-Nielsen  

E-Print Network [OSTI]

Current-voltage model of LED light sources Szymon Bczkowski, Stig Munk-Nielsen Department of Energy shifts caused by varying magnitude of LED driving current and nonlinear relationship between intensity radiation into visible light, are gradually being replaced by light-emitting diodes. The invention of LEDs

Munk-Nielsen, Stig

277

Arrays and Cascades of Fluorescent Liquid-Liquid Waveguides: Broadband Light Sources for  

E-Print Network [OSTI]

Arrays and Cascades of Fluorescent Liquid-Liquid Waveguides: Broadband Light Sources) microchannel waveguides with liquid cores containing fluorescent dyes, excited by incident light from an external halogen bulb. Simultaneous use of multiple fluorophores in a common solution, in a single L2 light

Prentiss, Mara

278

Solar Influences Light from the Sun is the largest source of energy for Earth's  

E-Print Network [OSTI]

Solar Influences Light from the Sun is the largest source of energy for Earth's atmosphere. The Solar Influences group at LASP studies the light from the Sun and how it interacts with the Earth) · How and why light from the Sun varies in time from seconds to months to years to centuries · How solar

Mojzsis, Stephen J.

279

Irradiation research capabilities at HFIR (High Flux Isotope Reactor) and ANS (Advanced Neutron Source)  

SciTech Connect (OSTI)

A variety of materials irradiation facilities exist in the High Flux Isotope Reactor (HFIR) and are planned for the Advanced Neutron Source (ANS) reactor. In 1986 the HFIR Irradiation Facilities Improvement (HIFI) project began modifications to the HFIR which now permit the operation of two instrumented capsules in the target region and eight capsules of 46-mm OD in the RB region. Thus, it is now possible to perform instrumented irradiation experiments in the highest continuous flux of thermal neutrons available in the western world. The new RB facilities are now large enough to permit neutron spectral tailoring of experiments and the modified method of access to these facilities permit rotation of experiments thereby reducing fluence gradients in specimens. A summary of characteristics of irradiation facilities in HFIR is presented. The ANS is being designed to provide the highest thermal neutron flux for beam facilities in the world. Additional design goals include providing materials irradiation and transplutonium isotope production facilities as good, or better than, HFIR. The reference conceptual core design consists of two annular fuel elements positioned one above the other instead of concentrically as in the HFIR. A variety of materials irradiation facilities with unprecedented fluxes are being incorporated into the design of the ANS. These will include fast neutron irradiation facilities in the central hole of the upper fuel element, epithermal facilities surrounding the lower fuel element, and thermal facilities in the reflector tank. A summary of characteristics of irradiation facilities presently planned for the ANS is presented. 2 tabs.

Thoms, K.R.

1990-01-01T23:59:59.000Z

280

A Population of Ultraluminous X-ray Sources with An Accreting Neutron Star  

E-Print Network [OSTI]

Most ultraluminous X-ray sources (ULXs) are believed to be X-ray binary systems, but previous observational and theoretical studies tend to prefer a black hole rather than a neutron star accretor. The recent discovery of 1.37 s pulsations from the ULX M82 X-2 has established its nature as a magnetized neutron star. In this work we model the formation history of neutron star ULXs in an M82- or Milky Way-like galaxy, by use of both binary population synthesis and detailed binary evolution calculations. We find that the birthrate is around $10^{-4}\\, \\rm yr^{-1}$ for the incipient X-ray binaries in both cases. We demonstrate the distribution of the ULX population in the donor mass - orbital period plane. Our results suggest that, compared with black hole X-ray binaries, neutron star X-ray binaries may significantly contribute to the ULX population, and high-mass and intermediate-mass X-ray binaries dominate the neutron star ULX population in M82- and Milky Way-like galaxies, respectively.

Shao, Yong

2015-01-01T23:59:59.000Z

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


281

EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator  

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

04: Linac Coherent Light Source II at Stanford Linear 04: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California Summary This EA evaluates the environmental impacts of the proposed construction of the Linac Coherent Light Source at SLAC National Accelerator Laboratory, Menlo Park, California. Public Comment Opportunities None available at this time. For more information, contact: Mr. Dave Osugi DOE SLAC Site Office 2575 Sand Hill Road, MS8A Menlo Park, CA 94025 Electronic mail: dave.osugi@sso.science.doe.gov Documents Available for Download March 7, 2012 EA-1904: Finding of No Significant Impact Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, CA

282

EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator  

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

4: Linac Coherent Light Source II at Stanford Linear 4: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California Summary This EA evaluates the environmental impacts of the proposed construction of the Linac Coherent Light Source at SLAC National Accelerator Laboratory, Menlo Park, California. Public Comment Opportunities None available at this time. For more information, contact: Mr. Dave Osugi DOE SLAC Site Office 2575 Sand Hill Road, MS8A Menlo Park, CA 94025 Electronic mail: dave.osugi@sso.science.doe.gov Documents Available for Download March 7, 2012 EA-1904: Finding of No Significant Impact Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, CA

283

Design of a horizontal neutron reflectometer for the European Spallation Source  

E-Print Network [OSTI]

A design study of a horizontal neutron reflectometer adapted to the general baseline of the long pulse European Spallation Source (ESS) is presented. The instrument layout comprises solutions for the neutron guide, high-resolution pulse shaping and beam bending onto a sample surface being so far unique in the field of reflectometry. The length of this instrument is roughly 55 m, enabling $\\delta \\lambda / \\lambda$ resolutions from 0.5% to 10%. The incident beam is focussed in horizontal plane to boost measurements of sample sizes of 1*1 cm{^2} and smaller with potential beam deflection in both downward and upward direction. The range of neutron wavelengths untilized by the instrument is 2 to 7.1 (12.2, ...) {\\AA}, if every (second, ...) neutron source ulse is used. Angles of incidence can be set between 0{\\deg} and 9{\\deg} with a total accessible q-range from 4*10^{-3} {\\AA}^{-1} up to 1 {\\AA}^{-1}. The instrument operates both in {\\theta}/{\\theta} (free liquid surfaces) and {\\theta}/2{\\theta} (solid/liquid, ...

Nekrassov, D; Lieutenant, K; Moulin, J -F; Strobl, M; Steitz, R

2013-01-01T23:59:59.000Z

284

Contributions of artificial lighting sources on light pollution in Hong Kong measured through a night sky brightness monitoring network  

E-Print Network [OSTI]

Light pollution is a form of environmental degradation in which excessive artificial outdoor lighting, such as street lamps, neon signs, and illuminated signboards, affects the natural environment and the ecosystem. Poorly designed outdoor lighting not only wastes energy, money, and valuable Earth resources, but also robs us of our beautiful night sky. Effects of light pollution on the night sky can be evaluated by the skyglow caused by these artificial lighting sources, through measurements of the night sky brightness (NSB). The Hong Kong Night Sky Brightness Monitoring Network (NSN) was established to monitor in detail the conditions of light pollution in Hong Kong. Monitoring stations were set up throughout the city covering a wide range of urban and rural settings to continuously measure the variations of the NSB. Over 4.6 million night sky measurements were collected from 18 distinct locations between May 2010 and March 2013. This huge dataset, over two thousand times larger than our previous survey, for...

Pun, Chun Shing Jason; Leung, Wai Yan; Wong, Chung Fai

2014-01-01T23:59:59.000Z

285

A Permanent-Magnet Microwave Ion Source for a Compact High-Yield Neutron Generator  

SciTech Connect (OSTI)

We present recent work on the development of a microwave ion source that will be used in a high-yield compact neutron generator for active interrogation applications. The sealed tube generator will be capable of producing high neutron yields, 5x1011 n/s for D-T and ~;;1x1010 n/s for D-D reactions, while remaining transportable. We constructed a microwave ion source (2.45 GHz) with permanent magnets to provide the magnetic field strength of 87.5 mT necessary for satisfying the electron cyclotron resonance (ECR) condition. Microwave ion sources can produce high extracted beam currents at the low gas pressures required for sealed tube operation and at lower power levels than previously used RF-driven ion sources. A 100 mA deuterium/tritium beam will be extracted through a large slit (60x6 mm2) to spread the beam power over a larger target area. This paper describes the design of the permanent-magnet microwave ion source and discusses the impact of the magnetic field design on the source performance. The required equivalent proton beam current density of 40 mA/cm2 was extracted at a moderate microwave power of 400 W with an optimized magnetic field.

Waldmann, Ole; Ludewigt, Bernhard

2010-10-11T23:59:59.000Z

286

High-speed low-voltage ultraviolet light source  

Science Journals Connector (OSTI)

A novel quasi-spark gap has been designed and constructed with high-speed and low-spark voltage characteristics. Ultraviolet light generating sparks can be operated at a rate of up to...

Huang, L; Hsu, S C; Kwok, H S

1984-01-01T23:59:59.000Z

287

ACHIEVING THE REQUIRED COOLANT FLOW DISTRIBUTION FOR THE ACCELERATOR PRODUCTION OF TRITIUM (APT) TUNGSTEN NEUTRON SOURCE  

SciTech Connect (OSTI)

The Accelerator Production of Tritium neutron source consists of clad tungsten targets, which are concentric cylinders with a center rod. These targets are arranged in a matrix of tubes, producing a large number of parallel coolant paths. The coolant flow required to meet thermal-hydraulic design criteria varies with location. This paper describes the work performed to ensure an adequate coolant flow for each target for normal operation and residual heat-removal conditions.

D. SIEBE; K. PASAMEHMETOGLU

2000-11-01T23:59:59.000Z

288

An Optically Stabilized Fast-Switching Light Emitting Diode as a Light Source for Functional  

E-Print Network [OSTI]

experimental setups. This paper presents a method to control the brightness of a high-power light emitting

Daniel A. Wagenaar

289

Underwater Lighting by Submerged Lasers and Incandescent Sources  

E-Print Network [OSTI]

and collimated underwater incandescent projector. The laser-collimated underwater incandescent projector used for beamBY SUBMERGED LASERS and Incandescent Sources DESCRIPTIVE

Duntley, Seibert Q

1971-01-01T23:59:59.000Z

290

Design of an RFQ-Based Neutron Source for Cargo ContainerInterrogation  

SciTech Connect (OSTI)

An RFQ-based neutron generator system is described that produces pulsed neutrons for the active screening of sea-land cargo containers for the detection of shielded special nuclear materials (SNM).A microwave-driven deuteron source is coupled to an electrostatic LEBT that injects a 40 mA D+ beam into a 6 MeV, 5.1 meter-long 200 MHz RFQ.The RFQ has a unique beam dynamics design and is capable of operating at duty factors of 5 to 10 percent accelerating a D+ time-averaged current of up to 1.5 mA at 5 percent duty factor, including species and transmission loss. The beam is transported through a specially-designed thin window into a 2.5-atmosphere deuterium gas target. A high-frequency dipole magnet is used to scan the beam over the long dimension of the 5by 35 cm target window. The source will deliver a neutron flux of 1 cdot107 n/(cm2s) to the center of an empty cargo container. Details of the ion source, LEBT, RFQ beam dynamics and gas target design are presented.

Staples, John W.; Hoff, M.D.; Kwan, J.W.; Li, D.; Ludewigt, B.A.; Ratti, A.; Virostek, S.P.; Wells, R.P.

2006-08-01T23:59:59.000Z

291

Evaluation of two-stage system for neutron measurement aiming at increase in count rate at Japan Atomic Energy Agency-Fusion Neutronics Source  

SciTech Connect (OSTI)

In order to increase the count rate capability of a neutron detection system as a whole, we propose a multi-stage neutron detection system. Experiments to test the effectiveness of this concept were carried out on Fusion Neutronics Source. Comparing four configurations of alignment, it was found that the influence of an anterior stage on a posterior stage was negligible for the pulse height distribution. The two-stage system using 25 mm thickness scintillator was about 1.65 times the count rate capability of a single detector system for d-D neutrons and was about 1.8 times the count rate capability for d-T neutrons. The results suggested that the concept of a multi-stage detection system will work in practice.

Shinohara, K., E-mail: shinohara.koji@jaea.go.jp; Ochiai, K.; Sukegawa, A. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Ishii, K.; Kitajima, S. [Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, Miyagi 980-8579 (Japan); Baba, M. [Cyclotron and Radioisotope Center, Tohoku University, Sendai, Miyagi 980-8578 (Japan); Sasao, M. [Organization for Research Initiatives and Development, Doshisha University, Kyoto 602-8580 (Japan)

2014-11-15T23:59:59.000Z

292

Neutron Repulsion  

E-Print Network [OSTI]

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

Oliver K. Manuel

2011-02-08T23:59:59.000Z

293

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

SciTech Connect (OSTI)

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

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

2013-07-01T23:59:59.000Z

294

Ultra-small-angle neutron scattering from dense micrometre-sized colloidal systems: data evaluation and comparison with static light scattering  

Science Journals Connector (OSTI)

Application of the GIFT method works well for evaluation of both neutron and light scattering data, but multiple scattering must be kept negligible. The advantage of light scattering is the fast data acquisition, while USANS covers a wider q range.

Innerlohinger, J.

2006-03-12T23:59:59.000Z

295

Science at the Speed of Light: Advanced Photon Source  

ScienceCinema (OSTI)

An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest x-ray beams in the Western Hemisphere, and the research carried out by scientists using those x-rays.

Murray Gibson

2010-01-08T23:59:59.000Z

296

Science at the Speed of Light: Advanced Photon Source  

SciTech Connect (OSTI)

An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest x-ray beams in the Western Hemisphere, and the research carried out by scientists using those x-rays.

Murray Gibson

2009-06-03T23:59:59.000Z

297

Thermal neutron detection system  

DOE Patents [OSTI]

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.

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

2000-01-01T23:59:59.000Z

298

Advances in 14 MeV neutron activation analysis by means of a new intense neutron source  

Science Journals Connector (OSTI)

A new intense 14 MeV neutron generator with cylindrical acceleration structure has been put in operation at the GKSS Research Center Geesthacht. The sealed neutron tube is combined with...10 n/cm2s. Theoretical s...

R. Pepelnik; H. -U. Fanger; W. Michaelis; B. Anders

1982-01-01T23:59:59.000Z

299

Accelerating Data Acquisition, Reduction, and Analysis at the Spallation Neutron Source  

SciTech Connect (OSTI)

ORNL operates the world's brightest neutron source, the Spallation Neutron Source (SNS). Funded by the US DOE Office of Basic Energy Science, this national user facility hosts hundreds of scientists from around the world, providing a platform to enable break-through research in materials science, sustainable energy, and basic science. While the SNS provides scientists with advanced experimental instruments, the deluge of data generated from these instruments represents both a big data challenge and a big data opportunity. For example, instruments at the SNS can now generate multiple millions of neutron events per second providing unprecedented experiment fidelity but leaving the user with a dataset that cannot be processed and analyzed in a timely fashion using legacy techniques. To address this big data challenge, ORNL has developed a near real-time streaming data reduction and analysis infrastructure. The Accelerating Data Acquisition, Reduction, and Analysis (ADARA) system provides a live streaming data infrastructure based on a high-performance publish subscribe system, in situ data reduction, visualization, and analysis tools, and integration with a high-performance computing and data storage infrastructure. ADARA allows users of the SNS instruments to analyze their experiment as it is run and make changes to the experiment in real-time and visualize the results of these changes. In this paper we describe ADARA, provide a high-level architectural overview of the system, and present a set of use-cases and real-world demonstrations of the technology.

Campbell, Stuart I [ORNL; Kohl, James Arthur [ORNL; Granroth, Garrett E [ORNL; Miller, Ross G [ORNL; Doucet, Mathieu [ORNL; Stansberry, Dale V [ORNL; Proffen, Thomas E [ORNL; Taylor, Russell J [ORNL; Dillow, David [None

2014-01-01T23:59:59.000Z

300

Intense Pulsed Neutron Source: Progress report 1991--1996. 15. Anniversary edition -- Volume 1  

SciTech Connect (OSTI)

The 15th Anniversary Edition of the IPNS Progress Report is being published in recognition of the Intense Pulsed Neutron Source`s first 15 years of successful operation as a user facility. To emphasize the importance of this milestone, the authors have made the design and organization of the report significantly different from previous IPNS Progress Reports. This report consists of two volumes. For Volume 1, authors were asked to prepare articles that highlighted recent scientific accomplishments at IPNS, from 1991 to present; to focus on and illustrate the scientific advances achieved through the unique capabilities of neutron studies performed by IPNS users; to report on specific activities or results from an instrument; or to focus on a body of work encompassing different neutron-scattering techniques. Articles were also included on the accelerator system, instrumentation, computing, target, and moderators. A list of published and ``in press` articles in journals, books, and conference proceedings, resulting from work done at IPNS since 1991, was compiled. This list is arranged alphabetically according to first author. Publication references in the articles are listed by last name of first author and year of publication. The IPNS experimental reports received since 1991 are compiled in Volume 2. Experimental reports referenced in the articles are listed by last name of first author, instrument designation, and experiment number.

Marzec, B. [ed.

1996-05-01T23:59:59.000Z

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


301

High-performance beam-plasma neutron sources for fusion materials development  

SciTech Connect (OSTI)

The design and performance of a relatively low-cost, plasma-based, 14-MeV deuterium-tritium neutron source for accelerated end-of-life testing of fusion reactor materials are described. An intense flux (up to 5 [times] 10[sup 18] n/m[sup 2][center dot]s) of 14-MeV neutrons is produced in a fully ionized high-density tritium target (n[sub e] [approx] 3 [times] 10[sup 21] m[sup [minus]3]) by injecting a current of 150-keV deuterium atoms. The tritium plasma target and the energetic D[sup +] density produced by D[sup 0] injection are confined in a [<=] 0.16-m-diam column by a linear magnet set, which provides magnetic fields up to 12 T. Energy deposited by transverse injection of neutral beams at the midpoint of the column is transported along the plasma column to the end regions. Three variations of the neutron source design are discussed, differing in the method of control of the energy transport. Emphasis is on the design in which the target plasma density is maintained in a region where electron thermal conduction along the column is the controlling energy-loss process.

Coensgen, F.H.; Casper, T.A.; Correll, D.L.; Damm, C.C.; Futch, A.H.; Logan, B.G.; Molvik, A.W. (Lawrence Livermore National Lab., CA (United States))

1990-10-01T23:59:59.000Z

302

Ion source and beam guiding studies for an API neutron generator  

SciTech Connect (OSTI)

Recently developed neutron imaging methods require high neutron yields for fast imaging times and small beam widths for good imaging resolution. For ion sources with low current density to be viable for these types of imaging methods, large extraction apertures and beam focusing must be used. We present recent work on the optimization of a Penning-type ion source for neutron generator applications. Two multi-cusp magnet configurations have been tested and are shown to increase the extracted ion current density over operation without multi-cusp magnetic fields. The use of multi-cusp magnetic confinement and gold electrode surfaces have resulted in increased ion current density, up to 2.2 mA/cm{sup 2}. Passive beam focusing using tapered dielectric capillaries has been explored due to its potential for beam compression without the cost and complexity issues associated with active focusing elements. Initial results from first experiments indicate the possibility of beam compression. Further work is required to evaluate the viability of such focusing methods for associated particle imaging (API) systems.

Sy, A. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 USA and Department of Nuclear Engineering, University of California, Berkeley, Berkeley, CA 94720 (United States); Ji, Q.; Persaud, A.; Ludewigt, B. A.; Schenkel, T. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

2013-04-19T23:59:59.000Z

303

Shielding analysis and design of the KIPT experimental neutron source facility of Ukraine.  

SciTech Connect (OSTI)

Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the conceptual design development of an experimental neutron source facility based on the use of an electron accelerator driven subcritical (ADS) facility [1]. The facility uses the existing electron accelerators of KIPT in Ukraine. The neutron source of the sub-critical assembly is generated from the interaction of 100 KW electron beam with a natural uranium target. The electron beam has a uniform spatial distribution and the electron energy in the range of 100 to 200 MeV, [2]. The main functions of the facility are the production of medical isotopes and the support of the Ukraine nuclear power industry. Reactor physics experiments and material performance characterization will also be carried out. The subcritical assembly is driven by neutrons generated by the electron beam interactions with the target material. A fraction of these neutrons has an energy above 50 MeV generated through the photo nuclear interactions. This neutron fraction is very small and it has an insignificant contribution to the subcritical assembly performance. However, these high energy neutrons are difficult to shield and they can be slowed down only through the inelastic scattering with heavy isotopes. Therefore the shielding design of this facility is more challenging relative to fission reactors. To attenuate these high energy neutrons, heavy metals (tungsten, iron, etc.) should be used. To reduce the construction cost, heavy concrete with 4.8 g/cm{sup 3} density is selected as a shielding material. The iron weight fraction in this concrete is about 0.6. The shape and thickness of the heavy concrete shield are defined to reduce the biological dose equivalent outside the shield to an acceptable level during operation. At the same time, special attention was give to reduce the total shield mass to reduce the construction cost. The shield design is configured to maintain the biological dose equivalent during operation {le} 0.5 mrem/h inside the subcritical hall, which is five times less than the allowable dose for working forty hours per week for 50 weeks per year. This study analyzed and designed the thickness and the shape of the radial and top shields of the neutron source based on the biological dose equivalent requirements inside the subcritical hall during operation. The Monte Carlo code MCNPX is selected because of its capabilities for transporting electrons, photons, and neutrons. Mesh based weight windows variance reduction technique is utilized to estimate the biological dose outside the shield with good statistics. A significant effort dedicated to the accurate prediction of the biological dose equivalent outside the shield boundary as a function of the shield thickness without geometrical approximations or material homogenization. The building wall was designed with ordinary concrete to reduce the biological dose equivalent to the public with a safety factor in the range of 5 to 20.

Zhong, Z.; Gohar, M. Y. A.; Naberezhnev, D.; Duo, J.; Nuclear Engineering Division

2008-10-31T23:59:59.000Z

304

Characteristics of a RF-Driven Ion Source for a Neutron Generator Used for Associated Particle Imaging  

SciTech Connect (OSTI)

We present recent work on a prototype compact neutron generator for associated particle imaging (API). API uses alpha particles that are produced simultaneously with neutrons in the deuterium-tritium ({sup 2}D({sup 3}T,n){sup 4}{alpha}) fusion reaction to determine the direction of the neutrons upon exiting the reaction. This method determines the spatial position of each neutron interaction and requires the neutrons to be generated from a small spot in order to achieve high spatial resolution. The ion source for API is designed to produce a focused ion beam with a beam spot diameter of 1-mm or less on the target. We use an axial type neutron generator with a predicted neutron yield of 10{sup 8} n/s for a 50 {mu}A D/T ion beam current accelerated to 80 kV. The generator utilizes an RF planar spiral antenna at 13.56 MHz to create a highly efficient inductively coupled plasma at the ion source. Experimental results show that beams with an atomic ion fraction of over 80% can be obtained while utilizing only 100 watts of RF power in the ion source. A single acceleration gap with a secondary electron suppression electrode is used in the tube. Experimental results from ion source testing, such as the current density, atomic ion fraction, electron temperature, and electron density will be discussed.

Wu Ying; Leung, K.-N. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Department of Nuclear Engineering, University of California-Berkeley, Berkeley, CA 94720 (United States); Hurley, John P. [Special Technologies Laboratory, Santa Barbara, CA 93111 (United States); Ji Qing; Kwan, Joe [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

2009-03-10T23:59:59.000Z

305

A comparison of four direct geometry time-of-flight spectrometers at the Spallation Neutron Source  

SciTech Connect (OSTI)

The Spallation Neutron Source at Oak Ridge National Laboratory now hosts four direct geometry time-of-flight chopper spectrometers. These instruments cover a range of wave-vector and energy transfer space with varying degrees of neutron flux and resolution. The regions of reciprocal and energy space available to measure at these instruments are not exclusive and overlap significantly. We present a direct comparison of the capabilities of this instrumentation, conducted by data mining the instrument usage histories, and specific scanning regimes. In addition, one of the common science missions for these instruments is the study of magnetic excitations in condensed matter systems. We have measured the powder averaged spin wave spectra in one particular sample using each of these instruments, and use these data in our comparisons.

Stone, M. B.; Abernathy, D. L.; Ehlers, G.; Garlea, O.; Podlesnyak, A.; Winn, B. [Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Niedziela, J. L.; DeBeer-Schmitt, L.; Graves-Brook, M. [Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Granroth, G. E. [Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Kolesnikov, A. I. [Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2014-04-15T23:59:59.000Z

306

A comparison of four direct geometry time-of-flight spectrometers at the Spallation Neutron Source  

SciTech Connect (OSTI)

The Spallation Neutron Source at Oak Ridge National Laboratory now hosts four direct geometry time-of-flight chopper spectrometers. These instruments cover a range of wave vector and energy transfer space with varying degrees of neutron flux and resolution. The regions of reciprocal and energy space available to measure at these instruments is not exclusive and overlaps significantly. We present a direct comparison of the capabilities of this instrumentation, conducted by data mining the instrument usage histories, and specific scanning regimes. In addition, one of the common science missions for these instruments is the study of magnetic excitations in condensed matter systems. We have measured the powder averaged spin wave spectra in one particular sample using each of these instruments, and use these data in our comparisons.

Stone, Matthew B [ORNL] [ORNL; Niedziela, Jennifer L [ORNL] [ORNL; Abernathy, Douglas L [ORNL] [ORNL; Debeer-Schmitt, Lisa M [ORNL] [ORNL; Garlea, Vasile O [ORNL] [ORNL; Granroth, Garrett E [ORNL] [ORNL; Graves-Brook, Melissa K [ORNL] [ORNL; Ehlers, Georg [ORNL] [ORNL; Kolesnikov, Alexander I [ORNL] [ORNL; Podlesnyak, Andrey A [ORNL] [ORNL; Winn, Barry L [ORNL] [ORNL

2014-01-01T23:59:59.000Z

307

Integrating advanced materials simulation techniques into an automated data analysis workflow at the Spallation Neutron Source  

SciTech Connect (OSTI)

This presentation will review developments on the integration of advanced modeling and simulation techniques into the analysis step of experimental data obtained at the Spallation Neutron Source. A workflow framework for the purpose of refining molecular mechanics force-fields against quasi-elastic neutron scattering data is presented. The workflow combines software components to submit model simulations to remote high performance computers, a message broker interface for communications between the optimizer engine and the simulation production step, and tools to convolve the simulated data with the experimental resolution. A test application shows the correction to a popular fixed-charge water model in order to account polarization effects due to the presence of solvated ions. Future enhancements to the refinement workflow are discussed. This work is funded through the DOE Center for Accelerating Materials Modeling.

Borreguero Calvo, Jose M [ORNL] [ORNL; Campbell, Stuart I [ORNL] [ORNL; Delaire, Olivier A [ORNL] [ORNL; Doucet, Mathieu [ORNL] [ORNL; Goswami, Monojoy [ORNL] [ORNL; Hagen, Mark E [ORNL] [ORNL; Lynch, Vickie E [ORNL] [ORNL; Proffen, Thomas E [ORNL] [ORNL; Ren, Shelly [ORNL] [ORNL; Savici, Andrei T [ORNL] [ORNL; Sumpter, Bobby G [ORNL] [ORNL

2014-01-01T23:59:59.000Z

308

Oak Ridge Reservation site evaluation report for the Advanced Neutron Source  

SciTech Connect (OSTI)

The Advanced Neutron Source (ANS) is a research reactor that is the US Department of Energy (DOE) plans to build for initial service late in this century. The primary purpose of the ANS is to provide a useable neutron flux for scattering experiments 5 to 10 times as a high as that generated by any existing research reactor, secondary purposes include production of a variety of transuranic and other isotopes and irradiation of materials. The ANS is proposed to be located on the DOE Oak Ridge Reservation (ORR) at Oak Ridge, Tennessee, and operated by the Oak Ridge National Laboratory (ORNL). This report documents the evaluation of alternative sites on the ORR and the selection of a site for the ANS.

Sigmon, B.; Heitzman, A.C. Jr.; Morrissey, J. (Science Applications International Corp., Oak Ridge, TN (United States))

1990-03-01T23:59:59.000Z

309

Status and Prospects of Coherent Light Source Developments at UVSOR-II  

SciTech Connect (OSTI)

We are developing coherent light sources at the UVSOR-II electron storage ring. We have developed a resonator type free electron laser in the visible to the deep UV range, coherent harmonic generation source in VUV range and coherent synchrotron radiation source in the terahertz range. A new five year plan has been started from FY2008, where a new 4m straight section will be created by moving the beam injection point, a new optical klystron type undulator will be installed and dedicated beam-lines will be constructed. Great advances on the coherent light source developments at the new straight section are expected.

Adachi, Masahiro; Katoh, Masahiro; Zen, Heishun; Tanikawa, Takanori [UVSOR Facility, Institute for Molecular Science, National Institute of Natural Sciences, Okazaki, 444-8585 (Japan); School of Physical Sciences, Graduate University for Advanced Sciences, Okazaki, 444-8585 (Japan); Hosaka, Masahito; Takashima, Yoshifumi; Yamamoto, Naoto; Taira, Yoshitaka [Graduate School of Engineering, Nagoya University, Nagoya, 464-8603 (Japan)

2010-06-23T23:59:59.000Z

310

Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory  

SciTech Connect (OSTI)

The yearly environmental dose equivalent likely to result at the closest site boundary from the Advanced Light Source was determined by generating multiple linear regressions. The independent variables comprised quantified accelerator operating parameters and measurements from synchronized, in-close (outside shielding prior to significant atmospheric scattering), state-of-the-art neutron remmeters and photon G-M tubes. Neutron regression models were more successful than photon models due to lower relative background radiation and redundant detectors at the site boundary. As expected, Storage Ring Beam Fill and Beam Crashes produced radiation at a higher rate than gradual Beam Decay; however, only the latter did not include zero in its 95% confidence interval. By summing for all three accelerator operating modes, a combined yearly DE of 4.3 mRem/yr with a 90% CI of (0.04-8.63) was obtained. These results fall below the DOE reporting level of 10 mRem/yr and suggest repeating the study with improved experimental conditions.

Ajemian, R.C. [Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Environmental Sciences and Engineering

1995-12-31T23:59:59.000Z

311

Dynamics of laser-produced Sn microplasma for a high-brightness extreme ultraviolet light source  

E-Print Network [OSTI]

EUV light source is excessive in terms of power, cost, and size foot- print . An HVM lithography etendue on the order of 0.03 mm2 sr , and bright several watts of power . This means that the focal spot

Najmabadi, Farrokh

312

High-Precision Fluorimetry with a Light-Emitting Diode Source  

Science Journals Connector (OSTI)

A simple fluorimeter which uses a light-emitting diode as a source of excitation and a photodiode as a detector has been constructed and evaluated. The exceptional stability of both...

Smith, B W; Jones, B T; Winefordner, J D

1988-01-01T23:59:59.000Z

313

Heat power capacity of the internal source in light-transparent coatings of planar solar collectors  

Science Journals Connector (OSTI)

The results are presented of numerical determination of the heat power capacity of the internal source in light-transparent coatings of planar solar collectors; the power results from partial absorption ... of th...

R. R. Avezov; N. R. Avezova; S. L. Lutpullaev; K. A. Samiev

2007-09-01T23:59:59.000Z

314

Quantum Cascade Lasers: New Resonant Tunnelling Light Sources for the Mid-Infrared  

Science Journals Connector (OSTI)

15 October 1996 research-article Quantum Cascade Lasers: New Resonant Tunnelling Light Sources...Hutchinson A. Y. Cho Recent results on quantum cascade lasers are reviewed. In these quantum devices based on resonant tunnelling the...

1996-01-01T23:59:59.000Z

315

Light source and CO2 concentration affect growth and anthocyanin content of lettuce under controlled environment  

Science Journals Connector (OSTI)

The effect of light source and CO2 concentration on the growth and anthocyanin content of lettuce (Lactuca sativa L. Seonhong Jeokchukmyeon) grown in growth chambers was examined. The plant was grown under 140 ...

Yoo Gyeong Park; Ji Eun Park

2012-12-01T23:59:59.000Z

316

Long-Distance FBG Sensor System Using High-Speed Swept-Wavelength Light Source  

Science Journals Connector (OSTI)

A long-distance FBG sensor system using a power controlled high-speed swept-wavelength light source is proposed and demonstrated. This system can measure FBGs reflection wavelengths...

Saitoh, Takanori; Nakamura, Kenichi; Takahashi, Yoshifumi; Iida, Hiroyuki; Iki, Yoshimitsu; Miyagi, Koichiro

317

Ramsey Experiments Using Neutron Beams  

Science Journals Connector (OSTI)

Abstract Ramsey's technique of separated oscillatory fields adapted to cold neutron beams is a very sensitive method to probe for spin- dependent interactions of neutrons with magnetic and pseudomagnetic fields. In the last couple of years several distinctive experiments using this technique have been performed, e.g. to determine the incoherent neutron scattering length of the deuteron, to perform polarized neutron imaging of magnetic fields and samples, and lately, to search for new light spin-1 bosons. Here, some of these results are reviewed and possible future measurements with respect to a pulsed neutron source are presented.

Florian M. Piegsa

2014-01-01T23:59:59.000Z

318

Environmental Assessment for the National Synchrotron Light Source II at Brookhaven National Laboratory  

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

NATIONAL SYNCHROTRON LIGHT SOURCE-II NATIONAL SYNCHROTRON LIGHT SOURCE-II (NSLS-II) BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK U. S. Department Of Energy Brookhaven Site Office September 2006 DOE/EA-1558 i TABLE OF CONTENTS 1.0 PREFACE....................................................................................................................1 2.0 SUMMARY .................................................................................................................2 3.0 PURPOSE AND NEED ............................................................................................10 4.0 DESCRIPTION OF ALTERNATIVES, INCLUDING THE PROPOSED ACTION.....................................................................................................................11

319

Volume-scalable high-brightness three-dimensional visible light source  

DOE Patents [OSTI]

A volume-scalable, high-brightness, electrically driven visible light source comprises a three-dimensional photonic crystal (3DPC) comprising one or more direct bandgap semiconductors. The improved light emission performance of the invention is achieved based on the enhancement of radiative emission of light emitters placed inside a 3DPC due to the strong modification of the photonic density-of-states engendered by the 3DPC.

Subramania, Ganapathi; Fischer, Arthur J; Wang, George T; Li, Qiming

2014-02-18T23:59:59.000Z

320

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

E-Print Network [OSTI]

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

Beaucage, Gregory

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


321

Advanced light ion source extraction system for a new electron cyclotron resonance ion source geometry at Saclay  

SciTech Connect (OSTI)

One of the main goal of intense light ion injector projects such as IPHI, IFMIF, or SPIRAL2, is to produce high current beams while keeping transverse emittance as low as possible. To prevent emittance growth induced in a dual solenoid low energy transfer line, its length has to be minimized. This can be performed with the advanced light ion source extraction system concept that we are developing: a new ECR 2.45 GHz type ion source based on the use of an additional low energy beam transport (LEBT) short length solenoid close to the extraction aperture to create the resonance in the plasma chamber. The geometry of the source has been considerably modified to allow easy maintenance of each component and to save space in front of the extraction. The source aims to be very flexible and to be able to extract high current ion beams at energy up to 100 kV. A specific experimental setup for this source is under installation on the BETSI test bench, to compare its performances with sources developed up to now in the laboratory, such as SILHI, IFMIF, or SPIRAL2 ECR sources. This original extraction source concept is presented, as well as electromagnetic simulations with OPERA-2D code. Ion beam extraction in space charge compensation regime with AXCEL, and beam dynamics simulation with SOLMAXP codes show the beam quality improvement at the end of the LEBT.

Delferriere, O.; Gobin, R.; Harrault, F.; Nyckees, S.; Sauce, Y.; Tuske, O. [Commissariat a l'Energie Atomique, CEA/Saclay, DSM/IRFU, 91191 Gif/Yvette (France)

2012-02-15T23:59:59.000Z

322

Long lifetime, low intensity light source for use in nighttime viewing of equipment maps and other writings  

DOE Patents [OSTI]

A long-lifetime light source with sufficiently low intensity to be used for reading a map or other writing at nighttime, while not obscuring the user's normal night vision. This light source includes a diode electrically connected in series with a small power source and a lens properly positioned to focus at least a portion of the light produced by the diode.

Frank, Alan M. (Livermore, CA); Edwards, William R. (Modesto, CA)

1983-01-01T23:59:59.000Z

323

Real Time Tomography at the Swiss Light Source  

SciTech Connect (OSTI)

The penetrating power of X-rays coupled with the high flux of 3rd generation synchrotron sources makes X-ray tomography to excel among fast imaging methods . To exploit this asset of synchrotron sources is the motivation for setting up an ultra-fast tomography endstation at the TOMCAT beamline. The state of the art instruments at synchrotron sources offer routinely a temporal resolution of tens of seconds in tomography. For a number of applications, for example biomedical studies, the relevant time scales (breathing, heartbeat) are rather in the range of 0.5-2 seconds. To overcome motion artifacts when imaging such systems a new ultra-fast tomographic data acquisition scheme is being developed at the TOMCAT beamline. We can acquire a full set of projections at sub-second timescale in monochromatic or white-beam configuration. We present a feasibility study with the ultimate aim to achieve sub-second temporal resolution in 3D without significant deterioration of the spatial resolution. For the first time, the 3D dynamics of the very early stages of a quickly aging liquid foam can be visualised with high quality and sufficiently large field of view.

Mokso, R.; Marone, F. [Swiss Light Source, Paul Scherrer Institut, 5232 Villigen (Switzerland); Stampanoni, M. [Swiss Light Source, Paul Scherrer Institut, 5232 Villigen (Switzerland); Institute for Biomedical Engineering, University and ETH Zurich, Zurich (Switzerland)

2010-06-23T23:59:59.000Z

324

Electron cloud development in the Proton Storage Ring and in the Spallation Neutron Source  

Science Journals Connector (OSTI)

We have applied our simulation code POSINST to evaluate the contribution to the growth rate of the electron cloud instability in proton storage rings. In particular, we present here recent simulation results for the main features of the electron cloud in the storage ring of the Spallation Neutron Source at Oak Ridge, and updated results for the Proton Storage Ring at Los Alamos. A key ingredient in our model is a detailed description of the secondary electron emission process, including a refined model for the emitted energy spectrum, and for the three main components of the secondary yield, namely, the true secondary, rediffused and backscattered components.

M. T. F. Pivi and M. A. Furman

2003-03-05T23:59:59.000Z

325

New Light on Improving Engine Efficiencies | Advanced Photon Source  

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

The Crystal Structure of a Meta-stable Intermediate Particle in Virus The Crystal Structure of a Meta-stable Intermediate Particle in Virus Assembly Increasing Magnetic Response of Ferromagnetic Semiconductors under High Pressure Better Switching Through Chemistry in Thin Ferroelectrics First Molecular-Level Enzyme Images Could Improve Breast-Cancer Therapy Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed New Light on Improving Engine Efficiencies MARCH 3, 2009 Bookmark and Share The DOE, as part of its Clean Coal & Natural Gas Power Systems initiative, has a "Turbines of Tomorrow" program with the Program Performance Goal to: "By 2010, develop turbine technology that is capable of efficiently

326

Photon Sciences | Operating the National Synchrotron Light Source,  

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

Science Highlights Science Highlights high-resolution scanning transmission electron microscopy image Nanocrystal Catalyst Transforms Impure Hydrogen into Electricity September 18, 2013 Brookhaven Lab scientists use simple, 'green' process to create novel core-shell catalyst that tolerates carbon monoxide in fuel cells and opens new, inexpensive pathways for zero-emission vehicles. Organic Solar Cells Shedding New Light on the 'Electron Highways' of Organic Solar Cells August 30, 2013 Researchers at Brookhaven Lab and Stony Brook University have developed a way to map out the degree of "traffic congestion" on the electron highways within the photoactive layer of organic solar cells. Li-ion Batteries For Better Li-ion Batteries, Scientists Watch One at Work August 29, 2013

327

Imaging spectroscopic analysis at the Advanced Light Source  

SciTech Connect (OSTI)

One of the major advances at the high brightness third generation synchrotrons is the dramatic improvement of imaging capability. There is a large multi-disciplinary effort underway at the ALS to develop imaging X-ray, UV and Infra-red spectroscopic analysis on a spatial scale from. a few microns to 10nm. These developments make use of light that varies in energy from 6meV to 15KeV. Imaging and spectroscopy are finding applications in surface science, bulk materials analysis, semiconductor structures, particulate contaminants, magnetic thin films, biology and environmental science. This article is an overview and status report from the developers of some of these techniques at the ALS. The following table lists all the currently available microscopes at the. ALS. This article will describe some of the microscopes and some of the early applications.

MacDowell, A. A.; Warwick, T.; Anders, S.; Lamble, G.M.; Martin, M.C.; McKinney, W.R.; Padmore, H.A.

1999-05-12T23:59:59.000Z

328

Luminescent light source for laser pumping and laser system containing same  

DOE Patents [OSTI]

The invention relates to a pumping lamp for use with lasers comprising a porous substrate loaded with a component capable of emitting light upon interaction of the component with exciting radiation and a source of exciting radiation. Preferably, the pumping lamp comprises a source of exciting radiation, such as an electron beam, and an aerogel or xerogel substrate loaded with a component capable of interacting with the exciting radiation, e.g., a phosphor, to produce light, e.g., visible light, of a suitable band width and of a sufficient intensity to generate a laser beam from a laser material.

Hamil, Roy A. (Tijeras, NM); Ashley, Carol S. (Albuquerque, NM); Brinker, C. Jeffrey (Albuquerque, NM); Reed, Scott (Albuquerque, NM); Walko, Robert J. (Albuquerque, NM)

1994-01-01T23:59:59.000Z

329

Design progress of cryogenic hydrogen system for China Spallation Neutron Source  

SciTech Connect (OSTI)

China Spallation Neutron Source (CSNS) is a large proton accelerator research facility with 100 kW beam power. Construction started in October 2011 and is expected to last 6.5 years. The cryogenic hydrogen circulation is cooled by a helium refrigerator with cooling capacity of 2200 W at 20 K and provides supercritical hydrogen to neutron moderating system. Important progresses of CSNS cryogenic system were concluded as follows. Firstly, process design of cryogenic system has been completed including helium refrigerator, hydrogen loop, gas distribution, and safety interlock. Secondly, an accumulator prototype was designed to mitigate pressure fluctuation caused by dynamic heat load from neutron moderation. Performance test of the accumulator has been carried out at room and liquid nitrogen temperature. Results show the accumulator with welding bellows regulates hydrogen pressure well. Parameters of key equipment have been identified. The contract for the helium refrigerator has been signed. Mechanical design of the hydrogen cold box has been completed, and the hydrogen pump, ortho-para hydrogen convertor, helium-hydrogen heat exchanger, hydrogen heater, and cryogenic valves are in procurement. Finally, Hydrogen safety interlock has been finished as well, including the logic of gas distribution, vacuum, hydrogen leakage and ventilation. Generally, design and construction of CSNS cryogenic system is conducted as expected.

Wang, G. P.; Zhang, Y.; Xiao, J.; He, C. C.; Ding, M. Y.; Wang, Y. Q.; Li, N.; He, K. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P.R. (China)

2014-01-29T23:59:59.000Z

330

Hydraulic testing of modified neutron source rod in type Q septifoil  

SciTech Connect (OSTI)

A Type Q septifoil, two modified partial length control rods, four full length control rods, a source rod containing a dummy neutron source and a guide tube assembly were installed in the Long Term Flow Facility (LTFF) of the HTL. The water level inside the guide tubes over the septifoil was measured by the use of sight tubes connected to pressure taps on the guide tubes or by pressure gages. Pressures were measured at tank bottom and inside the septifoil. The target tank bottom pressure for the experiments was 12.76 psig which gives the same no-flow freeboard in the LTFF as a blanket gas pressure of 5.00 psig in K Reactor. The first series of tests was performed with the existing source rods under a previous Task Plan, 92-057-1. The source rod was kept fully seated during testing to reduce the effect of the flow path through the source rod. Freeboards were adequate during the conditions of normal operation, but inadequate during scram conditions. The minimum freeboard measured during a scram for a septifoil flow of 106 gpm was 20 inches and 7 inches for 120 gpm, adjusted to the target tank bottom pressure. During a control rod scram the full length control rods are driven into the reactor core as a gauge. The reason that freeboards are small during a scram is that the rods pass through positions that tend to reduce freeboard, rather than the velocity of the rods having a negative effect. In fact, a lower freeboard occurs if the rod are held motionless at certain positions. The second series of tests was performed with a modified source rod in which the flow path through the source rod was eliminated. for these tests the source rod was lifted after the control rods had been positioned, the usual procedure in SRS Reactors. The source rod design change increased freeboards such that they were adequate under all conditions.

Steimke, J.L.; Fowley, M.D.

1992-10-01T23:59:59.000Z

331

White lighting LEDs are fast replacing conventional lighting because not only are they energy efficient light sources but also can be modulated at frequencies up to 20MHz for high-speed wireless communication, especially for indoor applications.  

E-Print Network [OSTI]

are they energy efficient light sources but also can be modulated at frequencies up to 20MHz for high-speedBackground White lighting LEDs are fast replacing conventional lighting because not only wireless communication, especially for indoor applications. Moreover, using visible light as the source

Sekercioglu, Y. Ahmet

332

La premire pierre de la source europenne de neutrons ESS, Lund Communiqu de presse, le 10 octobre 2014  

E-Print Network [OSTI]

La première pierre de la source européenne de neutrons ESS, à Lund (Suède) Communiqué de presse, le 10 octobre 2014 La construction de ESS, l'European Spallation Source (ESS). La première pierre de ce grand

van Tiggelen, Bart

333

Photon Sciences | Operating the National Synchrotron Light Source,  

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

Program Coordinator Program Coordinator Jun Wang Physicist, Industrial Program Coordinator Phone: 344-2661 Email: junwang@bnl.gov Jun Wang is an Industrial Program Coordinator in the Photon Science Directorate at Brookhaven National Laboratory. She is working closely with industrial researchers as well as beamline staff to identify and explore new opportunities in industrial applications using synchrotron radiation. She has been leading the industrial research program including consultation, collaboration and outreach to the industrial user groups. Before joining BNL in 2008, Jun Wang was a Lead Scientist for a high-resolution high throughput powder diffraction program at the Advanced Photon Source (APS). As a Physicist at BNL, her research focuses on materials structure determination and evolution. Her expertise covers wide

334

Intrinsic Lorentz violation in Doppler effect from a moving point light source  

E-Print Network [OSTI]

Einstein's Doppler formula is not applicable when a moving point light source is close enough to the observer; for example, it may break down or cannot specify a determinate value when the point source and the observer overlap. In this paper, Doppler effect for a moving point light source is analyzed, and it is found that the principle of relativity allows the existence of intrinsic Lorentz violation. A conceptual scheme to experimentally test the point-source Doppler effect is proposed, and such a test could lead to an unexpected result that the frequency of a photon may change during propagation, which questions the constancy of Planck constant since the energy conservation in Einstein's light-quantum hypothesis must hold.

Changbiao Wang

2010-07-06T23:59:59.000Z

335

Light Well: ATunable Free-Electron Light Source on a Chip K. F. MacDonald,1,* Y. H. Fu,2  

E-Print Network [OSTI]

Light Well: ATunable Free-Electron Light Source on a Chip G. Adamo,1 K. F. MacDonald,1,* Y. H. Fu,2 and surface plasmon-polariton sources [1­5]. Electron- beam-induced radiation emission [6­8] is of particular-emitter displays [12]. The light well belongs to a broad family of free-electron- driven radiation sources wherein

Zheludev, Nikolay

336

Simultaneous usage of pinhole and penumbral apertures for imaging small scale neutron sources from inertial confinement fusion experiments  

SciTech Connect (OSTI)

Inertial confinement fusion experiments at the National Ignition Facility are designed to understand the basic principles of creating self-sustaining fusion reactions by laser driven compression of deuterium-tritium (DT) filled cryogenic plastic capsules. The neutron imaging diagnostic provides information on the distribution of the central fusion reaction region and the surrounding DT fuel by observing neutron images in two different energy bands for primary (13-17 MeV) and down-scattered (6-12 MeV) neutrons. From this, the final shape and size of the compressed capsule can be estimated and the symmetry of the compression can be inferred. These experiments provide small sources with high yield neutron flux. An aperture design that includes an array of pinholes and penumbral apertures has provided the opportunity to image the same source with two different techniques. This allows for an evaluation of these different aperture designs and reconstruction algorithms.

Guler, N.; Volegov, P.; Danly, C. R.; Grim, G. P.; Merrill, F. E.; Wilde, C. H. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States)

2012-10-15T23:59:59.000Z

337

Subcriticality measurements for coupled uranium metal cylinders using the /sup 252/Cf-source-driven neutron noise analysis method  

SciTech Connect (OSTI)

Experiments performed with two coupled uranium metal cylinders are the first application to coupled systems of the /sup 252/Cf-source-driven neutron noise analysis method for obtaining the subcritical neutron multiplication factor. These coaxial cylinders were separated axially by various thicknesses of either air or borated plaster between the flat surfaces. In all measurements, the /sup 252/Cf neutron source was located at the center of the outer flat surface of one cylinder, and the two detectors were located in three configurations. By comparing the subcriticality from the measurements performed with borated plaster separating the uranium cylinders to those separated by air, it was found that the neutron multiplication factor was always increased by the insertion of borated plaster between the cylinders, regardless of their separation.

Mihalezo, J.T.; King, W.T.; Blakeman, E.D.

1987-01-01T23:59:59.000Z

338

The fast neutron fluence and the activation detector activity calculations using the effective source method and the adjoint function  

SciTech Connect (OSTI)

This paper describes the application of effective source in forward calculations and the adjoint method to the solution of fast neutron fluence and activation detector activities in the reactor pressure vessel (RPV) and RPV cavity of a VVER-440 reactor. Its objective is the demonstration of both methods on a practical task. The effective source method applies the Boltzmann transport operator to time integrated source data in order to obtain neutron fluence and detector activities. By weighting the source data by time dependent decay of the detector activity, the result of the calculation is the detector activity. Alternatively, if the weighting is uniform with respect to time, the result is the fluence. The approach works because of the inherent linearity of radiation transport in non-multiplying time-invariant media. Integrated in this way, the source data are referred to as the effective source. The effective source in the forward calculations method thereby enables the analyst to replace numerous intensive transport calculations with a single transport calculation in which the time dependence and magnitude of the source are correctly represented. In this work, the effective source method has been expanded slightly in the following way: neutron source data were performed with few group method calculation using the active core calculation code MOBY-DICK. The follow-up neutron transport calculation was performed using the neutron transport code TORT to perform multigroup calculations. For comparison, an alternative method of calculation has been used based upon adjoint functions of the Boltzmann transport equation. Calculation of the three-dimensional (3-D) adjoint function for each required computational outcome has been obtained using the deterministic code TORT and the cross section library BGL440. Adjoint functions appropriate to the required fast neutron flux density and neutron reaction rates have been calculated for several significant points within the RPV and RPV cavity of the VVER-440 reacto rand located axially at the position of maximum power and at the position of the weld. Both of these methods (the effective source and the adjoint function) are briefly described in the present paper. The paper also describes their application to the solution of fast neutron fluence and detectors activities for the VVER-440 reactor. (authors)

Hep, J.; Konecna, A.; Krysl, V.; Smutny, V. [Calculation Dept., Skoda JS plc, Orlik 266, 31606 Plzen (Czech Republic)

2011-07-01T23:59:59.000Z

339

Nuclear Simulation and Radiation Physics Investigations of the Target Station of the European Spallation Neutron Source  

SciTech Connect (OSTI)

The European Spallation Neutron Source (ESS) delivers high-intensity pulsed particle beams with 5-MW average beam power at 1.3-GeV incident proton energy. This causes sophisticated demands on material and geometry choices and a very careful optimization of the whole target system. Therefore, complex and detailed particle transport models and computer code systems have been developed and used to study the nuclear assessment of the ESS target system. The purpose here is to describe the methods of calculation mainly based on the Monte Carlo code to show the performance of the ESS target station. The interesting results of the simulations of the mercury target system are as follows: time-dependent neutron flux densities, energy deposition and heating, radioactivity and afterheat, materials damage by radiation, and high-energy source shielding. The results are discussed in great detail. The validity of codes and models, further requirements to improve the methods of calculation, and the status of running and planned experiments are given also.

Filges, Detlef; Neef, Ralf-Dieter; Schaal, Hartwig [Forschungszentrum Juelich GmbH (Germany)

2000-10-15T23:59:59.000Z

340

Static light scattering and small-angle neutron scattering study on aggregated recombinant gelatin in aqueous solution  

E-Print Network [OSTI]

Static Light Scattering and Small-Angle Neutron Scattering Study on Aggregated Recombinant Gelatin in Aqueous Solution A. Ramzi 1, M. Sutter 2, W.E. Hennink 1, W. Jiskoot 1,2 1 Department of Pharmaceutics, UIPS, Utrecht University, The Netherlands...-angle neutron scattering (SANS) for detecting aggregation of recombinant gelatin in aqueous solution and to obtain structural information about the aggregates. Recombinant Gelatin: RG-15-His 5.6Ser 25.2Pro 1.9Lys 3.7His 34.2Gly 15.5Gln 5.2Glu 11.8Asn 1.2Ala...

Sutter, Marc

2006-10-25T23:59:59.000Z

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


341

Calculation of Ambient (H*(10)) and Personal (Hp(10)) Dose Equivalent from a 252Cf Neutron Source  

SciTech Connect (OSTI)

The purpose of this calculation is to calculate the neutron dose factors for the Sr-Cf-3000 neutron source that is located in the 318 low scatter room (LSR). The dose factors were based on the dose conversion factors published in ICRP-21 Appendix 6, and the Ambient dose equivalent (H*(10)) and Personal dose equivalent (Hp(10)) dose factors published in ICRP Publication 74.

Traub, Richard J.

2010-03-26T23:59:59.000Z

342

Apparatus and method for compensating for electron beam emittance in synchronizing light sources  

DOE Patents [OSTI]

A focused optical beam is used to change the path length of the core electrons in electron light sources thereby boosting their efficiency of conversion of electron beam energy to light. Both coherent light in the free electron laser and incoherent light in the synchrotron is boosted by this technique. By changing the path length of the core electrons by the proper amount, the core electrons are caused to stay in phase with the electrons in the outer distribution of the electron beam. This increases the fraction of the electron beam energy that is converted to light thereby improving the efficiency of conversion of energy to light and therefore boosting the power output of the free electron laser and synchrotron. 4 figs.

Neil, G.R.

1996-07-30T23:59:59.000Z

343

Effect of interaction with neutrons in matter on flavor conversion of super-light sterile neutrino with active neutrino  

E-Print Network [OSTI]

A super-light sterile neutrino was proposed to explain the absence of the expected upturn of the survival probability of low energy solar boron neutrinos. This is because this super-light sterile neutrino can oscillate efficiently with electron neutrino through a MSW resonance happened in Sun. One may naturally expect that a similar resonance should happen for neutrinos propagating in Earth matter. We study the flavor conversion of this super-light sterile neutrino with active neutrinos in Earth matter. We find that the scenario of the super-light sterile neutrino can easily pass through possible constraints from experiments which can test the Earth matter effect in oscillation of neutrinos. Interestinlgy, we find that this is because the naively expected resonant conversion disappears or is significantly suppressed due to the presence of a potential $V_n$ which arises from neutral current interaction of neutrino with neutrons in matter. In contrast, the neutron number density in the Sun is negligible and the effect of $V_n$ is effectively switched off. This enables the MSW resonance in Sun needed in oscillation of the super-light sterile neutrino with solar electron neutrinos. It's interesting to note that it is the different situation in the Sun and in the Earth that makes $V_n$ effectively turned off and turned on respectively. This observation makes the scenario of the super-light sterile neutrino quite interesting.

Wei Liao; Yuchen Luo; Xiao-Hong Wu

2014-03-11T23:59:59.000Z

344

6 GeV LIGHT SOURCE PROJECT COST ESTIMATING PROCEDURE LS-34  

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

GeV LIGHT SOURCE PROJECT GeV LIGHT SOURCE PROJECT COST ESTIMATING PROCEDURE LS-34 October 23, 1985 YC/AVR To maintain uniformity in estimating the cost requirements of the various components of the 6 GeV Light Source, the following procedure will be used by all the task groups. The procedure uses a Work Breakdown Structure (WBS) to break down the project into manageable, easy to estimate, components. The project is first broken down into major tasks or categories. Then each major division is continuously subdivided until the desired level of detail is achieved. This can be shown best by using the example of the WBS of the Aladdin Upgrade Project, excerpts of which are included in Appendix A. As shown in the example, the project is first divided into: 1.1 Project Management and Administration

345

Energy Recovered Light Source Technology at TJNAF | U.S. DOE Office of  

Office of Science (SC) Website

Energy Recovered Light Source Energy Recovered Light Source Technology at TJNAF Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & 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: sc.np@science.doe.gov More Information » Spinoff Archives Energy Recovered Light Source Technology at TJNAF Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Energy-recovered linac/TJNAF Free Electron Laser Developed at: Thomas Jefferson National Accelerator Facility, Brookhaven National

346

Construction of Thermal Neutron Calibration Fields Using a Graphite Pile and Americium-Beryllium Neutron Sources at KAERI  

Science Journals Connector (OSTI)

Neutron Measurements / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

B. H. Kim; S. M. Jun; J. S. Kim; K. S. Lim; J. L. Kim

347

Evaluation of White Light Sources For an Absolute Fiber Optic Sensor Readout System  

SciTech Connect (OSTI)

This report summarizes work done in pursuit of an absolute readout system for Fabry-Perot optics sensors such as those built both by FISO and LLNL. The use of white light results in a short coherence length reducing the ambiguity of the Fabry-Perot gap measurement which is required to readout the sensor. The light source coherence length is the critical parameter in determining the ability to build a relative or an absolute system. Optical sources such as lasers and LEDs are rather narrow in optical spectral bandwidth and have long coherence length. Thus, when used in interferometric sensor measurements, one fringe looks much like another and it is difficult to make an absolute measurement. In contrast, white light sources are much broader in spectral bandwidth and have very short coherence lengths making interferometry possible only over the coherence length, which can be 1 or 2 microns. The small number of fringes in the interferogram make it easier to calculate the centroid and to unambiguously determine the sensor gap. However, unlike LEDs and Lasers, white light sources have very low optical power when coupled into optical fibers. Although, the overall light output of a white light source can be hundreds of milliwatts to watts, it is difficult to couple more than microwatts into a 50-micron core optical fiber. In addition, white light sources have a large amount of optical power in spectrum that is not necessarily useful in terms of sensor measurements. The reflectivity of a quarter wave of Titanium Oxide is depicted in Figure 2. This coating of Titanium Oxide is used in the fabrication of the sensor. This figure shows that any light emitted at wavelengths shorter than 600 nm is not too useful for the readout system. A white light LED spectrum is depicted in Figure 3 and shows much of the spectrum below 600 nm. In addition Silicon photodiodes are usually used in the readout system limiting the longest wavelength to about 1100 nm. Tungsten filament sources may have much of their optical power at wavelengths longer than 1100 nm, which is outside the wavelength range of interest. An incandescent spectrum from a tungsten filament is depicted in Figure 4. None of this is to say that other types of readout systems couldn't be built with IR detectors and broadband coatings for the sensors. However, without reengineering the sensors, the wavelength restrictions must be tolerated.

McConaghy, C F

2003-10-10T23:59:59.000Z

348

Diffraction and Transmission Synchrotron Imaging at the German Light Source ANKA--Potential Industrial Applications  

SciTech Connect (OSTI)

Diffraction and transmission synchrotron imaging methods have proven to be highly suitable for investigations in materials research and non-destructive evaluation. The high flux and spatial coherence of X-rays from modern synchrotron light sources allows one to work using high resolution and different contrast modalities. This article gives a short overview of different transmission and diffraction imaging methods with high potential for industrial applications, now available for commercial access via the German light source ANKA (Forschungszentrum Karlsruhe) and its new department ANKA Commercial Service (ANKA COS, http://www.anka-cos.de)

Rack, Alexander; Weitkamp, Timm [Institute for Synchrotron Radiation-ANKA, Forschungszentrum Karlsruhe/K.I.T., Postfach 3640, D-76021 Karlsruhe (Germany); European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France); Helfen, Lukas; Simon, Rolf; Luebbert, Daniel; Baumbach, Tilo [Institute for Synchrotron Radiation-ANKA, Forschungszentrum Karlsruhe/K.I.T., Postfach 3640, D-76021 Karlsruhe (Germany); Danilewsky, Andreas N. [Crystallographic Institute, University Freiburg, Hermann-Herder-Str. 5, D-79104 Freiburg (Germany)

2009-03-10T23:59:59.000Z

349

High-resolution VUV spectroscopy: New results from the Advanced Light Source  

SciTech Connect (OSTI)

Third-generation synchrotron light sources are providing photon beams of unprecedented brightness for researchers in atomic and molecular physics. Beamline 9.0.1, an undulator beamline at the Advanced Light Source (ALS), produces a beam in the vacuum-ultraviolet (VUV) region of the spectrum with exceptional flux and spectral resolution. Exciting new results from experiments in atomic and molecular VUV spectroscopy of doubly excited autoionizing states of helium, hollow lithium, and photoelectron spectroscopy of small molecules using Beamline 9.0.1 at the ALS are reported.

Schlachter, F.; Bozek, J.

1996-06-01T23:59:59.000Z

350

DOE/EIS0247; Final Environmental Impact Statement Construction and Operation of the Spallation Neutron Source  

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

SNS FEIS SNS FEIS Cover Sheet COVER SHEET RESPONSIBLE AGENCY: U.S. Department of Energy (DOE) TITLE: Final Environmental Impact Statement (FEIS), Construction and Operation of the Spallation Neutron Source (DOE/EIS-0247) LOCATIONS OF ALTERNATIVE SITES: Illinois, New Mexico, New York, and Tennessee. CONTACT: For further information on this document, write or call: Mr. David Wilfert, EIS Document Manager Oak Ridge Operations Office U.S. Department of Energy 200 Administration Road, 146/FEDC Oak Ridge, TN 37831 Telephone: (800) 927-9964 Facsimile: (423) 576-4542 E-mail: NSNSEIS@ornl.gov Mr. Jeff Hoy, SNS Program Manager Office of Basic Energy Research U.S. Department of Energy (ER-10) Germantown, MD 20874 Telephone: (301) 903-4924 Facsimile: (301) 903-9513 E-mail: Jeff.Hoy@mailgw.er.doe.gov

351

Record of Decision for the Construction and Operation of the Spallation Neutron Source  

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

140 140 Federal Register / Vol. 64, No. 125 / Wednesday, June 30, 1999 / Notices or minimize environmental harm that may result from implementing the Redevelopment Plan. Accordingly, Navy will dispose of the surplus Federal property at Naval Air Station Barbers Point in a manner that is consistent with the State of Hawaii's Redevelopment Plan for the property. Dated: June 17, 1999. William J. Cassidy, Jr., Deputy Assistant Secretary of the Navy (Conversion And Redevelopment). Dated: June 25, 1999. Ralph W. Corey, CDR, JAGC, USN, Alternate Federal Register Liaison Officer. [FR Doc. 99-16691 Filed 6-29-99; 8:45 am] BILLING CODE 3810-FF-M DEPARTMENT OF ENERGY Record of Decision for the Construction and Operation of the Spallation Neutron Source AGENCY: Department of Energy. ACTION: Record of decision.

352

Numerical studies of the flux-to-current ratio method in the KIPT neutron source facility  

SciTech Connect (OSTI)

The reactivity of a subcritical assembly has to be monitored continuously in order to assure its safe operation. In this paper, the flux-to-current ratio method has been studied as an approach to provide the on-line reactivity measurement of the subcritical system. Monte Carlo numerical simulations have been performed using the KIPT neutron source facility model. It is found that the reactivity obtained from the flux-to-current ratio method is sensitive to the detector position in the subcritical assembly. However, if multiple detectors are located about 12 cm above the graphite reflector and 54 cm radially, the technique is shown to be very accurate in determining the k{sub eff} this facility in the range of 0.75 to 0.975. (authors)

Cao, Y.; Gohar, Y.; Zhong, Z. [Nuclear Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

2013-07-01T23:59:59.000Z

353

EXPERIENCE WITH COLLABORATIVE DEVELOPMENT FOR THE SPALLATION NEUTRON SOURCE FROM A PARTNER LAB PERSPECTIVE.  

SciTech Connect (OSTI)

Collaborative development and operation of large physics experiments is fairly common. Less common is the collaborative development or operation of accelerators. A current example of the latter is the Spallation Neutron Source (SNS). The SNS project was conceived as a collaborative effort between six DOE facilities. In the SNS case, the control system was also developed collaboratively. The SNS project has now moved beyond the collaborative development phase and into the phase where Oak Ridge National Lab (ORNL) is integrating contributions from collaborating ''partner labs'' and is beginning accelerator operations. In this paper, the author reflects on the benefits and drawbacks of the collaborative development of an accelerator control system as implemented for the SNS project from the perspective of a partner lab.

HOFF, L.T.

2005-10-10T23:59:59.000Z

354

Application of the modified neutron source multiplication method to the prototype FBR Monju  

SciTech Connect (OSTI)

The Modified Neutron Source Method (MNSM) is applied to the Monju reactor. This static method to estimate sub-criticality has already given good results on commercial Pressurized Water Reactors. The MNSM consists both in the extraction of the fundamental mode seen by a detector to avoid the effect of higher modes near sources, and the correction of flux distortion effects due to control rod movement. Among Monju's particularities that have a big influence on MNSM factors are: the presence of two californium sources and the position of the detector, which is located far from the core outside of the reactor vessel. The importance of spontaneous fission and ({alpha},n) reactions, which have increased during the shutdown period of 15 years, will also be discussed. In order to evaluate the detector count rate, an analytical propagation has been conducted from the reactor vessel. For two subcritical states, an estimation of the reactivity has been made and compared to experimental data obtained in the restart experiments at Monju (2010). Results indicate a good agreement between the MNSM reactivity and the reactivity measured with other methods. The reactivity dependence of the correction to apply to point kinetic equation is discussed. (authors)

Truchet, G. [Institut National des Sciences et Techniques Nucleaires, Centre CEA de Saclay, F-91191 Gif-sur-Yvette Cedex (France); Van Rooijen, W. F. G.; Shimazu, Y. [Research Inst. of Nuclear Engineering, Univ. of Fukui, Kanawa-cho 1-2-4, T 914-0055, Fukui-ken, Tsuruga-shi (Japan)

2012-07-01T23:59:59.000Z

355

Watching an uniformly moving source of light using a telescope and a frequency-meter  

E-Print Network [OSTI]

We propose a scenario that involves a stationary observer who detects a point like source of light moving with constant velocity at a constant altitude, using a telescope and a frequency-meter. We derive a formula for the angular velocity at which we should rotate the axis of the telescope and a formula that relates the proper period at which the source emits successive wave crests and the proper period at which the stationary observer receives them

Bernhard Rothenstein; Ioan Damian

2005-04-04T23:59:59.000Z

356

Breaking symmetry through speed-induced beam-deflection via centrifugation of the light source  

E-Print Network [OSTI]

The experiment proposed aims to evidence and to measure the deflection of light rays induced by the source speed upon emission, and to discern it from the aberration of light rays induced by the observer speed. The method stands in creating a speed asymmetry between that of the source and that of the observer, and relies on the centrifugation of a light source at ultrahigh speed. When source and observer have the same speed, such as when being both on the same inertial system, the deflection and the aberration compensate and their net effect is null. So, in order to circumscribe the odds of inertial systems and to isolate these speed-induced effects it has instead been appealed to a centrifugal system, since it allows infringing symmetry between the source and the observer speeds. Three cases are considered. (a) Centrifugation of the source fixed at one end of the rotor arm, while the detector is fixed on the rotor axis. This configuration of the experiment aims to unveil that due to the peripheral speed of the source the beam is deflected forward, so it impinges on the centric detector slightly shifted from its position when the system was not rotating. (b) The positions of the source and the detector are interchanged, so the source peripheral speed is then null and thus no speed-induced deflection ensues, but due to the observer peripheral speed there is a speed-induced aberration since during the beam time-of-flight the detector has slightly moved side-way. However, this time the spot shifts in opposite direction and hence the effect of centrifugation is not reciprocal. (c) The source and the detector are fixed at the two ends of the rotor arms. In this case the beam deflection and aberration add, since their speed vectors have opposite directions and each shift of the spot on the detector is double since the time-of-flight is double.

G. Sardin

2004-05-22T23:59:59.000Z

357

Radiation damage and lifetime estimation of the proton beam window at the Japan Spallation Neutron Source  

Science Journals Connector (OSTI)

Abstract The proton beam window (PBW) is a component that separates the high-vacuum area of the accelerator from the target area in the Japan Proton Accelerator Research Complexs Japan Spallation Neutron Source (JSNS). It is important to estimate the damage accumulated from proton beam irradiation to establish a safe lifetime for the window. The PBW is made of an aluminum alloy, which was chosen because of its successful use in the target safety hull of the Swiss Spallation Neutron Source (SINQ). Post-irradiation examination (PIE) performed on SINQ Target 3 after irradiation with a 0.6GeV proton beam measured the gas production in its aluminum safety hull. To estimate a safe lifetime for the JSNS PBW, we calculated the displacement per atom (DPA) and gas production rate using the Particle and Heavy Ion Transport code System (PHITS) for 0.6- and 3-GeV protons. For the hydrogen gas production rate, PHITS shows good agreement with the SINQ PIE results; however, for the helium production rate, it predicts a 45% lower value than the experimental result of 1125 appm. The calculated result for helium production was normalized to fit the experimental results of SINQ. We conservatively estimate the lifetime of the JSNS PBW using the condition that the hydrogen production rate does not exceed the value measured at SINQ. The lifetime of the PBW corresponds to a proton beam fluence of 1.8נ1021cm?2, which is equivalent to an integrated beam power of 8000MWh with the designed current density of 10?Acm?2. The peak density will be reduced to 8.4?Acm?2 to suppress cavitation pitting damage in the mercury target vessel. Consequently, the lifetime of the PBW will be 9500MWh.

Shin-ichiro Meigo; Motoki Ooi; Masahide Harada; Hidetaka Kinoshita; Atushi Akutsu

2014-01-01T23:59:59.000Z

358

Design of an Aluminum Proton Beam Window for the Spallation Neutron Source  

SciTech Connect (OSTI)

An aluminum proton beam window design is being considered at the Spallation Neutron Source primarily to increase the lifetime of the window, with secondary advantages of higher beam transport efficiency and lower activation. The window separates the core vessel, the location of the mercury target, from the vacuum of the accelerator, while withstanding the pass through of a proton beam of up to 2 MW with 1.0 GeV proton energy. The current aluminum alloy being investigated for the window material is 6061-T651 due to its combination of high strength, high thermal conductivity, and good resistance to aqueous corrosion, as well as demonstrated dependability in previous high-radiation environments. The window design will feature a thin plate with closely spaced cross drilled cooling holes. An analytical approach was used to optimize the dimensions of the window before finite element analysis was used to simulate temperature profiles and stress fields resulting from thermal and static pressure loading. The resulting maximum temperature of 60 C and Von Mises stress of 71 MPa are very low compared to allowables for Al 6061-T651. A significant challenge in designing an aluminum proton beam window for SNS is integrating the window with the current 316L SS shield blocks. Explosion bonding was chosen as a joining technique because of the large bonding area required. A test program has commenced to prove explosion bonding can produce a robust vacuum joint. Pending successful explosion bond testing, the aluminum proton beam window design will be proven acceptable for service in the Spallation Neutron Source.

Janney, Jim G [ORNL; McClintock, David A [ORNL

2012-01-01T23:59:59.000Z

359

Department of Energy review of the National Spallation Neutron Source Project  

SciTech Connect (OSTI)

A Department of Energy (DOE) review of the Conceptual Design Report (CDR) for the National Spallation Neutron Source (NSNS) was conducted. The NSNS will be a new high-power spallation neutron source; initially, it will operate at 1 megawatt (MW), but is designed to be upgradeable to significantly higher power, at lower cost, when accelerator and target technologies are developed for higher power. The 53-member Review Committee examined the projected cost, schedule, technical scope, and management structure described in the CDR. For each of the major components of the NSNS, the Committee determined that the project team had produced credible designs that can be expected to work well. What remains to be done is to integrate the design of these components. With the exception of the liquid mercury target, the NSNS Project will rely heavily on proven technologies and, thus, will face a relatively low risk to successful project completion. The Total Project Cost (TPC) presented to the Committee in the CDR was $1.266 billion in as-spent dollars. In general, the Committee felt that the laboratory consortium had presented a credible estimate for each of the major components but that value engineering might produce some savings. The construction schedule presented to the Committee covered six years beginning in FY 1999. The Committee questioned whether all parts of the project could be completed according to this schedule. In particular, the linac and the conventional facilities appeared to have overly optimistic schedules. The NSNS project team was encouraged to reexamine these activities and to consider a more conservative seven-year schedule. Another concern of the Committee was the management structure. In summary, the Committee felt that this Conceptual Design Report was a very credible proposal, and that there is a high probability for successful completion of this major project within the proposed budget, although the six-year proposed schedule may be optimistic.

NONE

1997-06-01T23:59:59.000Z

360

Light Source  

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

traditionally done on very small scale resources. BES software landscape is largely ad-hoc and relies heavily on a limited number of experts to handle analysis. Diversity at...

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


361

The measurement and analysis of the magnetic field of a synchrotron light source magnet  

E-Print Network [OSTI]

In this thesis a unique system is used to measure the magnetic field of a superconducting synchrotron light source magnet. The magnet measured is a superferric dipole C-magnet designed to produce a magnetic field up to 3 Tesla in magnitude. Its...

Graf, Udo Werner

2012-06-07T23:59:59.000Z

362

Preliminary design of a GD?NCT neutron beam based on compact D?T neutron source  

Science Journals Connector (OSTI)

......J. Roentgenol. 36 , 1-13 (1936). 2. Sweet, W. H. and Javid, M. The possible use of slow neutrons plus boron-10 in the therapy of intracranial tumors. Trans. Am. neurol. Ass. 76 , 60-63 (1951). 3. Sweet, W. H., Soloway......

N. Cerullo; J. Esposito; D. Bufalino; A. Mastrullo; L. Muzi; S. Palmerini

2005-12-20T23:59:59.000Z

363

Neutron range spectrometer  

DOE Patents [OSTI]

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.

Manglos, S.H.

1988-03-10T23:59:59.000Z

364

Comparative analysis of neutron sources produced by low-energy electrons and deuterons for driving subcritical assemblies.  

SciTech Connect (OSTI)

A conceptual design of an accelerator driven subcritical assembly has been developed using the existing accelerators at Kharkov Institute of Physics and Technology (KIPT) in Ukraine. Two different external neutron source options were examined for driving the subcritical assembly. Electrons with energies below 200 MeV and deuterons with energies below 100 MeV were considered. Comparative analysis of these two options is presented and discussed. The Comparative analysis of neutron sources produced by low-energy electrons and deuterons show that: (1) An electron accelerator with electron energy in the range of 150 to 200 MeV is preferred for producing neutron source; (2) The uranium target material produces the highest neutron yield per electron; (3) The uranium target with 100 KW electron beam produces 3.3 x 10{sup 14} n/s; (4) The thermal hydraulics analyses of the uranium target operating with the 100 KW electron beam power satisfy the engineering design requirements; and (5) The peak thermal stresses (secondary stress) is less than the yield strength of the uranium target material.

Naberezhnev, D.; Gohar, Y.; Belch, H.; Duo, J.; Bolshinsky, I. (Nuclear Engineering Division); (INL)

2008-04-10T23:59:59.000Z

365

The neutron drip line: single-particle degrees of freedom and pairing properties as sources of theoretical uncertainties  

E-Print Network [OSTI]

The sources of theoretical uncertainties in the prediction of the two-neutron drip line are analyzed in the framework of covariant density functional theory. We concentrate on single-particle and pairing properties as potential sources of these uncertainties. The major source of these uncertainties can be traced back to the differences in the underlying single-particle structure of the various covariant energy density functionals (CEDF). It is found that the uncertainties in the description of single-particle energies at the two-neutron drip line are dominated by those existing already in known nuclei. Only approximately one third of these uncertainties are due to the uncertainties in the isovector channel of CEDF's. Thus, improving the CEDF description of single-particle energies in known nuclei will also reduce the uncertainties in the prediction of the position of two-neutron drip line. The predictions of pairing properties in neutron rich nuclei depend on the CEDF. Although pairing properties affect moder...

Afanasjev, A V; Ray, D; Ray, P

2015-01-01T23:59:59.000Z

366

Light ion source for proton/deuteron production at CEA Saclay for the Spiral2 project  

SciTech Connect (OSTI)

The production of rare radioactive ion beam (RIB) far from the valley of stability is one of the final purposes of the Spiral2 facility in Caen. The RIB will be produced by impinging a deuteron beam onto a carbon sample to produce a high neutron flux, which will interact with a uranium target. The primary deuteron beam is produced by an ion source based on ECR plasma generation. The deuteron source and the low energy beam transport (LEBT) has been assembled and tested at CEA Saclay. Diagnostics from other laboratories were implemented on the LEBT in order to characterize the deuteron beam produced and compare it to the initial simulations. The ion source has been based on a SILHI-type source, which has demonstrated good performances in pulsed and continuous mode, and also a very good reliability on long term operation. The 5 mA of deuteron beam required at the RFQ entrance is extracted from the plasma source at the energy of 40 kV. After a brief description of the experimental set-up, this article reports on the first beam characterization experiments.

Tuske, O.; Adroit, G.; Delferriere, O.; Denis, J-F.; Gauthier, Y.; Girardot, P.; Gobin, R.; Harrault, F.; Guiho, P.; Sauce, Y.; Uriot, D.; Vacher, T.; Van Hille, C. [CEA/Saclay, DSM/IRFU/SACM, F- 91191-Gif/Yvette (France); Graehling, P.; Hosselet, J.; Maazouzi, C. [IPHC, Institut Pluridisciplinaire Hubert Curien, Strasbourg (France)

2012-02-15T23:59:59.000Z

367

Neutron Scattering Facilities 1982  

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

NEUTRON SOURCES NEUTRON SOURCES Types of Sources U.S. Sources Available for Users Plans for the Future The Neutron Scattering Society of America (NSSA) SNS/ANL School on Neutron and x-Ray Scattering, June 2011 Jim Rhyne Lujan Neutron Scattering Center Los Alamos National Lab. What do we need to do neutron scattering? * Neutron Source - produces neutrons * Diffractometer or Spectrometer - Allows neutrons to interact with sample - Sorts out discrete wavelengths by monochromator (reactor) or by time of flight (pulse source) - Detectors pick up neutrons scattered from sample * Analysis methods to determine material properties * Brain power to interpret results Sources of neutrons for scattering * Nuclear Reactor - Neutrons produced from fission of 235 U - Fission spectrum neutrons

368

Dual-etalon cavity ring-down frequency-comb spectroscopy with broad band light source  

DOE Patents [OSTI]

In an embodiment, a dual-etalon cavity-ring-down frequency-comb spectrometer system is described. A broad band light source is split into two beams. One beam travels through a first etalon and a sample under test, while the other beam travels through a second etalon, and the two beams are recombined onto a single detector. If the free spectral ranges ("FSR") of the two etalons are not identical, the interference pattern at the detector will consist of a series of beat frequencies. By monitoring these beat frequencies, optical frequencies where light is absorbed may be determined.

Chandler, David W; Strecker, Kevin E

2014-04-01T23:59:59.000Z

369

Pulsed spallation neutron source with an induction linac and a fixed-field alternating-gradient accelerator  

SciTech Connect (OSTI)

The paper describes an accelerator scenario of a Pulsed Spallation Neutron Source made of an Induction Linac injecting into a Fixed-Field Alternating-Gradient Accelerator (FFAG). The motivations underlying the proposal deal with the concern of removing technical risks peculiar to other scenarios involving RF Linacs, Synchrotrons and Accumulator Rings, which originate, for example, from the need of developing intense negative-ion sources and of multi-turn injection into the Compressor Rings. The system proposed here makes use of a positive-ion source of very short pulse duration, and of single-turn transfer into the circular accelerator.

Ruggiero, A.G. [Brookhaven National Lab., Upton, NY (United States); Bauer, G. [Paul Scherrer Institute, Villigen (Switzerland); Faltens, A. [Lawrence Berkeley National Lab., CA (United States)] [and others

1995-12-01T23:59:59.000Z

370

Light is one of the most important environmental factors for plants, as it provides the source of energy for plant  

E-Print Network [OSTI]

Light is one of the most important environmental factors for plants, as it provides the source of energy for plant life. It is therefore not surprising that plants have adopted the ability to sense multiple parameters of ambient light signals, including light quantity (fluence), quality (wavelength

Deng, Xing-Wang

371

Protein Structures Through use of Superbends at the Advance Light Source |  

Office of Science (SC) Website

Protein Structures Protein Structures Through use of Superbends at the Advance Light Source Laboratory Policy and Evaluation (LPE) LPE Home Staff M&O Contracts SC Laboratory Appraisal Process Laboratory Planning Process Work for Others in the Office of Science Laboratory Directed Research and Development (LDRD) DOE's Philosophy on LDRD Frequently Asked Questions Success Stories Brochures Additional Information LDRD Program Contacts Technology Transfer DOE National Laboratories Contact Information Laboratory Policy and Evaluation U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5447 F: (202) 586-3119 Success Stories Protein Structures Through use of Superbends at the Advance Light Source Print Text Size: A A A RSS Feeds FeedbackShare Page

372

Advanced Photon Source lights the way to 2012 Chemistry Nobel | Argonne  

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

Advanced Photon Source lights the way to 2012 Chemistry Nobel Advanced Photon Source lights the way to 2012 Chemistry Nobel By Jared Sagoff * October 10, 2012 Tweet EmailPrint ARGONNE, Ill. - Thanks in part to research performed at the U.S. Department of Energy's (DOE) Argonne National Laboratory, the 2012 Nobel Prize in Chemistry was awarded today to Americans Brian Kobilka and Robert Lefkowitz for their work on G-protein-coupled receptors. G-protein-coupled receptors, or GPCRs, are a large family of proteins embedded in a cell's membrane that sense molecules outside the cell and activate a cascade of different cellular processes in response. They constitute key components of how cells interact with their environments and are the target of nearly half of today's pharmaceuticals. These medicines work by connecting with many of the 800 or so human GPCRs.

373

SHIELDING ESTIMATES FOR THE ANL 6.0 GeV SYNCHROTRON LIGHT SOURCE  

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

SHIELDING ESTIMATES FOR THE ANL 6.0 GeV SHIELDING ESTIMATES FOR THE ANL 6.0 GeV SYNCHROTRON LIGHT SOURCE H. J. Moe V. R. Veluri LS-55-Revised Harch 1987 2 1.0 Introduction Shielding estimates for the linac, positron converter, booster synchrotron and the positron storage ring have been computed using preliminary design information. Calculations have been made of the resulting radiation for several types of operations involving normal beam loss, as well as, certain accidental beam losses. When available, experimental data from existing accelerator and light source facilities have been used in lieu of theoretical estimates. 2.0 Shielding Design Objective The Department of Energy's basic occupational exposure limit is 5 rem per year (DOE 81). However, in its guidance for maintaining exposures "as

374

FINDING OF NO SIGNIFICANT IMPACT FOR LINAC COHERENT LIGHT SOURCE-Il  

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

FINDING FINDING OF NO SIGNIFICANT IMPACT FOR LINAC COHERENT LIGHT SOURCE-Il PROJECT SLAC NATIONAL ACCELERATOR LABORATORY AGENCY: U. S. Department of Energy (DOE) ACTION: Finding of No Significant Impact (FONSI) SUMMARY: The U. S. Department of Energy (DOE) has completed an Environmental Assessment (DOE/EA-1904) on a project to expand the existing Linac Coherent Light Source (LCLS) facility at the SLAC National Accelerator Laboratory (SLAC). One of SLAC's major scientific facilities is the LCLS, the world's first hard X-ray free electron laser. The LCLS X-ray laser beams enable the simultaneous investigation of a material's electronic and structural properties on the size (sub-nanometer) and time (femto-second) scales that determine their function. Research programs at SLAC include materials science, catalytic sciences, structural molecular biology, and molecular environmental

375

Development of an electron gun for an ERL based light source in Japan  

SciTech Connect (OSTI)

We have developed a prototype DC photoemission electron gun for a future energy recovery linac (ERL) based light source in Japan. The prototype gun is operated at up to 250 kV and is designed to deliver up to 50 mA beam current. A diagnostic beam line for emittance and bunch length measurements has been constructed. We have also designed a new 500 kV DC gun which is capable of producing up to 10 mA electron current with emittance lower than 1 mm-mrad. The high voltage terminal will be isolated by ten ceramics stacked in series. The new gun will satisfy performance required as an injector for the compact ERL, which will be constructed at KEK site as a prototype of the future ERL light source.

Nishimori, N.; Nagai, R.; Iijima, H.; Hajima, R. [Japan Atomic Energy Agency (JAEA), Tokai, Naka, Ibaraki 319-1195 (Japan); Honda, Y.; Muto, T. [High Energy Accelerator Research Organization (KEK), Oho, Tsukuba, Ibaraki 305-0801 (Japan); Kuriki, M. [Hiroshima University, Kagamiyama, Higashihiroshima, Hiroshima 739-8530 (Japan); Yamamoto, M.; Okumi, S.; Nakanishi, T. [Graduate School of Science, Nagoya University, Nagoya 464-8602 (Japan)

2009-08-04T23:59:59.000Z

376

Low-Level Radio Frequency System Development for the National Synchrotron Light Source II  

SciTech Connect (OSTI)

The National Synchrotron Light Source-II (NSLS-II) is a new ultra-bright 3GeV 3rd generation synchrotron radiation light source. The performance goals require operation with a beam current of 500mA and a bunch current of at least 0.5mA. The position and timing specifications of the ultra-bright photon beam imposes a set of stringent requirements on the performance of radio frequency (RF) control. In addition, commissioning and staged installation of damping wigglers and insertion devices requires the flexibility of handling varying beam conditions. To meet these requirements, a digital implementation of the LLRF is chosen, and digital serial links are planned for the system integration. The first prototype of the controller front-end hardware has been built, and is currently being tested.

Ma,H.; Rose, J.

2009-05-04T23:59:59.000Z

377

National Synchrotron Light Source users manual: Guide to the VUV and x-ray beam lines  

SciTech Connect (OSTI)

The success of the National Synchrotron Light Source in the years to come will be based, in large part, on the size of the users community and the diversity of the scientific disciplines represented by these users. In order to promote this philosophy, this National Synchrotron Light Source (NSLS) Users Manual: Guide to the VUV and X-Ray Beam Lines, has been published. This manual serves a number of purposes. In an effort to attract new research, it will present to the scientific community-at-large the current and projected architecture and capabilities of the various VUV and x-ray beam lines and storage rings. We anticipate that this publication will be updated periodically in order to keep pace with the constant changes at the NSLS.

Gmuer, N.F.; White-DePace, S.M. (eds.)

1987-08-01T23:59:59.000Z

378

ZIRCONIUMHAFNIUM ISOTOPE EVIDENCE FROM METEORITES FOR THE DECOUPLED SYNTHESIS OF LIGHT AND HEAVY NEUTRON-RICH NUCLEI  

SciTech Connect (OSTI)

Recent work based on analyses of meteorite and terrestrial whole-rock samples showed that the r- and s- process isotopes of Hf were homogeneously distributed throughout the inner solar system. We report new Hf isotope data for Calcium-Aluminum-rich inclusions (CAIs) of the CV3 carbonaceous chondrite Allende, and novel high-precision Zr isotope data for these CAIs and three carbonaceous chondrites (CM, CO, CK). Our Zr data reveal enrichments in the neutron-rich isotope {sup 96}Zr (?1? in {sup 96}Zr/{sup 90}Zr) for bulk chondrites and CAIs (?2?). Potential isotope effects due to incomplete sample dissolution, galactic and cosmic ray spallation, and the nuclear field shift are assessed and excluded, leading to the conclusion that the {sup 96}Zr isotope variations are of nucleosynthetic origin. The {sup 96}Zr enrichments are coupled with {sup 50}Ti excesses suggesting that both nuclides were produced in the same astrophysical environment. The same CAIs also exhibit deficits in r-process Hf isotopes, which provides strong evidence for a decoupling between the nucleosynthetic processes that produce the light (A ? 130) and heavy (A > 130) neutron-rich isotopes. We propose that the light neutron-capture isotopes largely formed in Type II supernovae (SNeII) with higher mass progenitors than the supernovae that produced the heavy r-process isotopes. In the context of our model, the light isotopes (e.g. {sup 96}Zr) are predominantly synthesized via charged-particle reactions in a high entropy wind environment, in which Hf isotopes are not produced. Collectively, our data indicates that CAIs sampled an excess of materials produced in a normal mass (12-25 M{sub ?}) SNII.

Akram, W.; Schnbchler, M. [School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Sprung, P. [Institut fr Planetologie, Universitt Mnster, Wilhelm-Klemm-Strasse 10, D-48149 Mnster (Germany); Vogel, N. [Institute for Geochemistry and Petrology, ETH, Clausiusstrasse 25, 8092 Zrich (Switzerland)

2013-11-10T23:59:59.000Z

379

Environmental Assessment for Linac Coherent Light Source Experimental Facility (12/02)  

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

Stanford Stanford Linear A ccelerator Center DOE/EA-1426 Environmental Assessment for Linac Coherent Light Source Experimental Facility LCLS December 2002 LCLS Environmental Assessment DOE/EA-1426 December 2002 Page - i - Environmental Assessment for LCLS Experimental Facility Table of Contents Preface ............................................................................................................................................ iii 1.0 Summary ................................................................................................................................... 1 2.0 Purpose and Need for LCLS ..................................................................................................... 6 3.0 Description of Proposed Action and Alternatives

380

Time-resolved far-infrared experiments at the National Synchrotron Light Source. Final report  

SciTech Connect (OSTI)

A facility for time-resolved infrared and far-infrared spectroscopy has been built and commissioned at the National Synchrotron Light Source. This facility permits the study of time dependent phenomena over a frequency range from 2-8000cm{sup {minus}1} (0.25 meV-1 eV). Temporal resolution is approximately 200 psec and time dependent phenomena in the time range out to 100 nsec can be investigated.

Tanner, D.B.; Reitze, D.H.; Carr, G.L.

1999-10-12T23:59:59.000Z

Note: This page contains sample records for the topic "light sources neutron" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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to obtain the most current and comprehensive results.


381

EA-1975: LINAC Coherent Light Source-Il, SLAC National Accelerator Laboratory, Menlo Park, California  

Broader source: Energy.gov [DOE]

DOE is preparing an EA on the potential environmental impacts of a proposal to upgrade the existing LINAC Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory. The proposed LCLS-II would extend the photon energy range, increase control over photon pulses, and enable two-color pump-probe experiments. The X-ray laser beams generated by LCLS-II would enable a new class of experiments: the simultaneous investigation of a materials electronic and structural properties.

382

Comparison of linear optics measurement and correction methods at the Swiss Light Source  

Science Journals Connector (OSTI)

A systematic analysis of linear optics optimization using various independent methods has been performed. Three independent techniques, namely quadrupole variation, linear optics from closed orbits, and turn-by-turn measurement, have been studied at the Swiss Light Source. Furthermore, the performances are compared from various aspects including a direct comparison of the corrected optics. The limitations of the three independent methods are also presented.

M. Aiba; M. Bge; J. Chrin; N. Milas; T. Schilcher; A. Streun

2013-01-29T23:59:59.000Z

383

Characterization of an explosively bonded aluminum proton beam window for the Spallation Neutron Source  

SciTech Connect (OSTI)

An effort is underway at the Spallation Neutron Source (SNS) to change the design of the 1st Generation high-nickel alloy proton beam window (PBW) to one that utilizes aluminum for the window material. One of the key challenges to implementation of an aluminum PBW at the SNS was selection of an appropriate joining method to bond an aluminum window to the stainless steel bulk shielding of the PBW assembly. An explosively formed bond was selected as the most promising joining method for the aluminum PBW design. A testing campaign was conducted to evaluate the strength and efficacy of explosively formed bonds that were produced using two different interlayer materials: niobium and titanium. The characterization methods reported here include tensile testing, thermal-shock leak testing, optical microscopy, and advanced scanning electron microscopy. All tensile specimens examined failed in the aluminum interlayer and measured tensile strengths were all slightly greater than the native properties of the aluminum interlayer, while elongation values were all slightly lower. A leak developed in the test vessel with a niobium interlayer joint after repeated thermal-shock cycles, and was attributed to an extensive crack network that formed in a layer of niobium-rich intermetallics located on the bond interfaces of the niobium interlayer; the test vessel with a titanium interlayer did not develop a leak under the conditions tested. Due to the experience gained from these characterizations, the explosively formed bond with a titanium interlayer was selected for the aluminum PBW design at the SNS.

McClintock, David A [ORNL] [ORNL; Janney, Jim G [ORNL] [ORNL; Parish, Chad M [ORNL] [ORNL

2014-01-01T23:59:59.000Z

384

Characterization of irradiated AISI 316L stainless steel disks removed from the Spallation Neutron Source  

SciTech Connect (OSTI)

Irradiated AISI 316L stainless steel disks were removed from the Spallation Neutron Source (SNS) for post-irradiation examination (PIE) to assess mechanical property changes due to radiation damage and erosion of the target vessel. Topics reviewed include high-resolution photography of the disk specimens, cleaning to remove mercury (Hg) residue and surface oxides, profile mapping of cavitation pits using high frequency ultrasonic testing (UT), high-resolution surface replication, and machining of test specimens using wire electrical discharge machining (EDM), tensile testing, Rockwell Superficial hardness testing, Vickers microhardness testing, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The effectiveness of the cleaning procedure was evident in the pre- and post-cleaning photography and permitted accurate placement of the test specimens on the disks. Due to the limited amount of material available and the unique geometry of the disks, machine fixturing and test specimen design were critical aspects of this work. Multiple designs were considered and refined during mock-up test runs on unirradiated disks. The techniques used to successfully machine and test the various specimens will be presented along with a summary of important findings from the laboratory examinations.

Vevera, Bradley J [ORNL] [ORNL; Hyres, James W [ORNL] [ORNL; McClintock, David A [ORNL] [ORNL; Riemer, Bernie [ORNL] [ORNL

2014-01-01T23:59:59.000Z

385

Thermal-hydraulic criteria for the APT tungsten neutron source design  

SciTech Connect (OSTI)

This report presents the thermal-hydraulic design criteria (THDC) developed for the tungsten neutron source (TNS). The THDC are developed for the normal operations, operational transients, and design-basis accidents. The requirements of the safety analyses are incorporated into the design criteria, consistent with the integrated safety management and the safety-by-design philosophy implemented throughout the APT design process. The phenomenology limiting the thermal-hydraulic design and the confidence level requirements for each limit are discussed. The overall philosophy of the uncertainty analyses and the confidence level requirements also are presented. Different sets of criteria are developed for normal operations, operational transients, anticipated accidents, unlikely accidents, extremely unlikely accidents, and accidents during TNS replacement. In general, the philosophy is to use the strictest criteria for the high-frequency events. The criteria is relaxed as the event frequencies become smaller. The THDC must be considered as a guide for the design philosophy and not as a hard limit. When achievable, design margins greater than those required by the THDC must be used. However, if a specific event sequence cannot meet the THDC, expensive design changes are not necessary if the single event sequence results in sufficient margin to safety criteria and does not challenge the plant availability or investment protection considerations.

Pasamehmetoglu, K.

1998-03-01T23:59:59.000Z

386

Replacing a 252Cf source with a neutron generator in a shuffler - a conceptual design performed with MCNPX  

SciTech Connect (OSTI)

The {sup 252}Cf shuffler has been widely used in nuclear safeguards and radioactive waste management to assay fissile isotopes, such as {sup 235}U or {sup 239}Pu, present in a variety of samples, ranging from small cans of uranium waste to metal samples weighing several kilograms. Like other non-destructive assay instruments, the shuffler uses an interrogating neutron source to induce fissions in the sample. Although shufflers with {sup 252}Cf sources have been reliably used for several decades, replacing this isotopic source with a neutron generator presents some distinct advantages. Neutron generators can be run in a continuous or pulsed mode, and may be turned off, eliminating the need for shielding and a shuffling mechanism in the shuffler. There is also essentially no dose to personnel during installation, and no reliance on the availability of {sup 252}Cf. Despite these advantages, the more energetic neutrons emitted from the neutron generator (141 MeV for D-T generators) present some challenges for certain material types. For example when the enrichment of a uranium sample is unknown, the fission of {sup 238}U is generally undesirable. Since measuring uranium is one of the main uses of a shuffler, reducing the delayed neutron contribution from {sup 238}U is desirable. Hence, the shuffler hardware must be modified to accommodate a moderator configuration near the source to tailor the interrogating spectrum in a manner which promotes sub-threshold fissions (below 1 MeV) but avoids the over-moderation of the interrogating neutrons so as to avoid self-shielding. In this study, where there are many material and geometry combinations, the Monte Carlo N-Particle eXtended (MCNPX) transport code was used to model, design, and optimize the moderator configuration within the shuffler geometry. The code is then used to evaluate and compare the assay performances of both the modified shuffler and the current {sup 252}Cf shuffler designs for different test samples. The matrix effect and the non-uniformity of the interrogating flux are investigated and quantified in each case. The modified geometry proposed by this study can serve s a guide in retrofitting shufflers that are already in use.

Schear, Melissa A [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

387

A Neutron Resonance Capture Analysis Experimental Station at the ISIS Spallation Source  

Science Journals Connector (OSTI)

Neutron resonance capture analysis (NRCA) is a nuclear technique that is used to determine the elemental composition of materials and artifacts (e.g., bronze objects) of...

Pietropaolo, Antonino; Gorini, Giuseppe; Festa, Giulia; Reali, Enzo; Grazzi, Francesco; Schooneveld, Erik M

2010-01-01T23:59:59.000Z

388

Imaging of Diesel Particulate Filters using a High-Flux Neutron Source  

Broader source: Energy.gov [DOE]

Detailed images of deposits identified inside automotive DPFs using neutrons show how the deposits of soot, ash, and washcoat occurs within the filter.

389

Silicon Photo-Multiplier radiation hardness tests with a beam controlled neutron source  

E-Print Network [OSTI]

We report radiation hardness tests performed at the Frascati Neutron Generator on silicon Photo-Multipliers, semiconductor photon detectors built from a square matrix of avalanche photo-diodes on a silicon substrate. Several samples from different manufacturers have been irradiated integrating up to 7x10^10 1-MeV-equivalent neutrons per cm^2. Detector performances have been recorded during the neutron irradiation and a gradual deterioration of their properties was found to happen already after an integrated fluence of the order of 10^8 1-MeV-equivalent neutrons per cm^2.

M. Angelone; M. Pillon; R. Faccini; D. Pinci; W. Baldini; R. Calabrese; G. Cibinetto; A. Cotta Ramusino; R. Malaguti; M. Pozzati

2010-02-18T23:59:59.000Z

390

Instrument performance study on the short and long pulse options of the second Spallation Neutron Source target station  

SciTech Connect (OSTI)

The Spallation Neutron Source (SNS) facility at the Oak Ridge National Laboratory is designed with an upgrade option for a future low repetition rate, long wavelength second target station. This second target station is intended to complement the scientific capabilities of the 1.4 MW, 60 Hz high power first target station. Two upgrade possibilities have been considered, the short and the long pulse options. In the short pulse mode, proton extraction occurs after the pulse compression in the accumulator ring. The proton pulse structure is thus the same as that for the first target station with a pulse width of ?0.7 ?s. In the long pulse mode, protons are extracted as they are produced by the linac, with no compression in the accumulator ring. The time width of the uncompressed proton pulse is ?1 ms. This difference in proton pulse structure means that neutron pulses will also be different. Neutron scattering instruments thus have to be designed and optimized very differently for these two source options which will directly impact the overall scientific capabilities of the SNS facility. In order to assess the merits of the short and long pulse target stations, we investigated a representative suit of neutron scattering instruments and evaluated their performance under each option. Our results indicate that the short pulse option will offer significantly better performance for the instruments and is the preferred choice for the SNS facility.

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

2013-10-15T23:59:59.000Z

391

Design of a TOF-SANS instrument for the proposed Long Wavelength Target Station at the Spallation Neutron Source.  

SciTech Connect (OSTI)

We have designed a versatile high-throughput SANS instrument [Broad Range Intense Multipurpose SANS (BRIMS)] for the proposed Long Wavelength Target Station at the SNS by using acceptance diagrams and the Los Alamos NISP Monte Carlo simulation package. This instrument has been fully optimized to take advantage of the 10 Hz source frequency (broad wavelength bandwidth) and the cold neutron spectrum from a tall coupled solid methane moderator (12 cm x 20 cm). BRIMS has been designed to produce data in a Q range spanning from 0.001 to 0.7 {angstrom}{sup {minus}1} in a single measurement by simultaneously using neutrons with wavelengths ranging from 1 to 14.5 {angstrom} in a time of flight mode. A supermirror guide and bender assembly is employed to separate and redirect the useful portion of the neutron spectrum with {lambda} > 1 {angstrom}, by 2.3{degree} away from the direct beam containing high energy neutrons and {gamma} rays. The effects of the supermirror coating of the guide, the location of the bender assembly with respect to the source, the bend angle, and various collimation choices on the flux, resolution and Q{sub min} have been characterized using spherical particle and delta function scatterers. The overall performance of BRIMS has been compared with that of the best existing reactor-based SANS instrument D22 at ILL.

Thiyagarajan, P.; Littrell, K.; Seeger, P. A.

2000-11-28T23:59:59.000Z

392

DOE/EIS-0247; Draft Environmental Impact Statement Construction and Operation of the Spallation Neutron Source, December 1998  

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

December 1998 December 1998 Construction and Operation of the S PALLATION N EUTRON S OURCE DRAFT ENVIRONMENTAL IMPACT STATEMENT U.S. Department of Energy Office of Science DOE/EIS-0247 Construction and Operation of the Spallation Neutron Source Facility Draft Environmental Impact Statement U.S. Department of Energy Office of Science December 1998 DOE/EIS-0247 Draft, December 1998 Cover Sheet COVER SHEET RESPONSIBLE AGENCY: U.S. Department of Energy (DOE) TITLE: Draft Environmental Impact Statement (DEIS), Construction and Operation of the Spallation Neutron Source (DOE/EIS-0247) LOCATIONS OF ALTERNATIVE SITES: Illinois, New Mexico, New York, and Tennessee. CONTACT: For further information on this document, write or call: Mr. David Wilfert, EIS Document Manager U.S. Department of Energy Oak Ridge Operations Office

393

Concept for a Time-of-Flight Small Angle Neutron Scattering Instrument at the European Spallation Source  

E-Print Network [OSTI]

A new Small Angle Neutron Scattering instrument is proposed for the European Spallation Source. The pulsed source requires a time-of-flight analysis of the gathered neutrons at the detector. The optimal instrument length is found to be rather large, which allows for a polarizer and a versatile collimation. The polarizer allows for studying magnetic samples and incoherent background subtraction. The wide collimation will host VSANS and SESANS options that increase the resolution of the instrument towards um and tens of um, respectively. Two 1m2 area detectors will cover a large solid angle simultaneously. The expected gains for this new instrument will lie in the range between 20 and 36, depending on the assessment criteria, when compared to up-to-date reactor based instruments. This will open new perspectives for fast kinetics, weakly scattering samples, and multi-dimensional contrast variation studies.

S. Jaksch; D. Martin-Rodriguez; A. Ostermann; J. Jestin; S. Duarte Pinto; W. G. Bouwman; J. Uher; R. Engels; G. Kemmerling; R. Hanslik; H. Frielinghaus

2014-03-11T23:59:59.000Z

394

Development of nanodiamond foils for H- stripping to Support the Spallation Neutron Source (SNS) using hot filament chemical vapor deposition  

SciTech Connect (OSTI)

Thin diamond foils are needed in many particle accelerator experiments regarding nuclear and atomic physics, as well as in some interdisciplinary research. Particularly, nanodiamond texture is attractive for this purpose as it possesses a unique combination of diamond properties such as high thermal conductivity, mechanical strength and high radiation hardness; therefore, it is a potential material for energetic ion beam stripper foils. At the ORNL Spallation Neutron Source (SNS), the installed set of foils must be able to survive a nominal five-month operation period, without the need for unscheduled costly shutdowns and repairs. Thus, a small foil about the size of a postage stamp is critical to the operation of SNS and similar sources in U.S. laboratories and around the world. We are investigating nanocrystalline, polycrystalline and their admixture films fabricated using a hot filament chemical vapor deposition (HFCVD) system for H- stripping to support the SNS at Oak Ridge National Laboratory. Here we discuss optimization of process variables such as substrate temperature, process gas ratio of H2/Ar/CH4, substrate to filament distance, filament temperature, carburization conditions, and filament geometry to achieve high purity diamond foils on patterned silicon substrates with manageable intrinsic and thermal stresses so that they can be released as free standing foils without curling. An in situ laser reflectance interferometry tool (LRI) is used for monitoring the growth characteristics of the diamond thin film materials. The optimization process has yielded free standing foils with no pinholes. The sp3/sp2 bonds are controlled to optimize electrical resistivity to reduce the possibility of surface charging of the foils. The integrated LRI and HFCVD process provides real time information on the growth of films and can quickly illustrate growth features and control film thickness. The results are discussed in the light of development of nanodiamond foils that will be able to withstand a few MW proton beam and hopefully will be able to be used after possible future upgrades to the SNS to greater than a 3MW beam.

Vispute, R D [Blue Wave Semiconductors; Ermer, Henry K [Blue Wave Semiconductors; Sinsky, Phillip [Blue Wave Semiconductors; Seiser, Andrew [Blue Wave Semiconductors; Shaw, Robert W [ORNL; Wilson, Leslie L [ORNL

2014-01-01T23:59:59.000Z

395

Tagged Neutron Source for API Inspection Systems with Greatly Enhanced Spatial Resolution  

SciTech Connect (OSTI)

We recently developed induced fission and transmission imaging methods with time- and directionally-tagged neutrons offer new capabilities for characterization of fissile material configurations and enhanced detection of special nuclear materials (SNM). An Advanced Associated Particle Imaging (API) generator with higher angular resolution and neutron yield than existing systems is needed to fully exploit these methods.

None

2012-06-04T23:59:59.000Z

396

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

SciTech Connect (OSTI)

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

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

2013-07-15T23:59:59.000Z

397

Surface properties of neutron-rich exotic nuclei: A source for studying the nuclear symmetry energy  

E-Print Network [OSTI]

We study the correlation between the thickness of the neutron skin in finite nuclei and the nuclear symmetry energy for isotopic chains of even-even Ni, Sn, and Pb nuclei in the framework of the deformed self-consistent mean-field Skyrme HF+BCS method. The symmetry energy, the neutron pressure and the asymmetric compressibility in finite nuclei are calculated within the coherent density fluctuation model using the symmetry energy as a function of density within the Brueckner energy-density functional. The mass dependence of the nuclear symmetry energy and the neutron skin thickness are also studied together with the role of the neutron-proton asymmetry. A correlation between the parameters of the equation of state (symmetry energy and its density slope) and the neutron skin is suggested in the isotopic chains of Ni, Sn, and Pb nuclei.

Gaidarov, M K; Sarriguren, P; de Guerra, E Moya

2011-01-01T23:59:59.000Z

398

PERFORMING DIAGNOSTICS ON THE SPALLATION NEUTRON SOURCE VISION BEAM LINE TO ELIMINATE HIGH VIBRATION LEVELS AND PROVIDE A SUSTAINABLE OPERATION  

SciTech Connect (OSTI)

The Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory (ORNL) provides variable energy neutrons for a variety of experiments. The neutrons proceed down beam lines to the experiment hall, which houses a variety of experiments and test articles. Each beam line has one or more neutron choppers which filter the neutron beam based on the neutron energy by using a rotating neutron absorbing material passing through the neutron beam. Excessive vibration of the Vision beam line, believed to be caused by the T0 chopper, prevented the Vision beam line from operating at full capacity. This problem had been addressed several times by rebalancing/reworking the T0 beam chopper but the problem stubbornly persisted. To determine the cause of the high vibration, dynamic testing was performed. Twenty-seven accelerometer and motor current channels of data were collected during drive up, drive down, coast down, and steady-state conditions; resonance testing and motor current signature analysis were also performed. The data was analyzed for traditional mechanical/machinery issues such as misalignment and imbalance using time series analysis, frequency domain analysis, and operating deflection shape analysis. The analysis showed that the chopper base plate was experiencing an amplified response to the excitation provided by the T0 beam chopper. The amplified response was diagnosed to be caused by higher than expected base plate flexibility, possibly due to improper grouting or loose floor anchors. Based on this diagnosis, a decision was made to dismantle the beam line chopper and remount the base plate. Neutron activation of the beam line components make modifications to the beam line especially expensive and time consuming due to the radiation handling requirements, so this decision had significant financial and schedule implications. It was found that the base plate was indeed loose because of improper grouting during its initial installation. The base plate was modified by splitting it into multiple sections, isolating the T0 chopper from the rest of the beam line, and each section was then reinstalled and re-grouted. After these modifications, the vibration levels were reduced by a factor of 30. The reduction in vibration level was sufficient to allow the Vision beam line to operate at full capacity for the first time since its completed construction date.

Van Hoy, Blake W [ORNL

2014-01-01T23:59:59.000Z

399

Relative light yield and temporal response of a stilbene-doped bibenzyl organic scintillator for neutron detection  

SciTech Connect (OSTI)

The neutron time-of-flight (nTOF) diagnostics used to characterize implosions at the National Ignition Facility (NIF) has necessitated the development of novel scintillators that exhibit a rapid temporal response and high light yield. One such material, a bibenzyl-stilbene mixed single-crystal organic scintillator grown in a 99.5:0.5 ratio in solution, has become the standard scintillator used for nTOF diagnostics at NIF. The prompt fluorescence lifetime and relative light yield as a function of proton energy were determined to calibrate this material as a neutron detector. The temporal evolution of the intensity of the prompt fluorescent response was modeled using first-order reaction kinetics and the prompt fluorescence decay constant was determined to be 2.46??0.01 (fit)??0.13 (systematic) ns. The relative response of the bibenzyl-stilbene mixed crystal generated by recoiling protons was measured, and results were analyzed using Birks' relation to quantify the non-radiative quenching of excitation energy in the scintillator.

Brown, J. A.; Goldblum, B. L., E-mail: bethany@nuc.berkeley.edu; Brickner, N. M.; Daub, B. H.; Kaufman, G. S.; Bibber, K. van; Vujic, J. [Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Bernstein, L. A.; Bleuel, D. L.; Caggiano, J. A.; Hatarik, R.; Phillips, T. W.; Zaitseva, N. P. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Wender, S. A. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2014-05-21T23:59:59.000Z

400

Steady State Microbunching for High Brilliance and High Repetition Rate Storage Ring-Based Light Sources  

SciTech Connect (OSTI)

Electron-based light sources have proven to be effective sources of high brilliance, high frequency radiation. Such sources are typically either linac-Free Electron Laser (FEL) or storage ring types. The linac-FEL type has high brilliance (because the beam is microbunched) but low repetition rate. The storage ring type has high repetition rate (rapid beam circulation) but comparatively low brilliance or coherence. We propose to explore the feasibility of a microbunched beam in a storage ring that promises high repetition rate and high brilliance. The steady-state-micro-bunch (SSMB) beam in storage ring could provide CW sources for THz, EUV, or soft X-rays. Several SSMB mechanisms have been suggested recently, and in this report, we review a number of these SSMB concepts as promising directions for high brilliance, high repetition rate light sources of the future. The trick of SSMB lies in the RF system, together with the associated synchrotron beam dynamics, of the storage ring. Considering various different RF arrangements, there could be considered a number of scenarios of the SSMB. In this report, we arrange these scenarios more or less in order of the envisioned degree of technical challenge to the RF system, and not in the chronological order of their original references. Once the stored beam is steady-state microbunched in a storage ring, it passes through a radiator repeatedly every turn (or few turns). The radiator extracts a small fraction of the beam energy as coherent radiation with a wavelength corresponding to the microbunched period of the beam. In contrast to an FEL, this radiator is not needed to generate the microbunching (as required e.g. by SASE FELs or seeded FELs), so the radiator can be comparatively simple and short.

Chao, Alex; Ratner, Daniel; /SLAC; Jiao, Yi; /Beijing, Inst. High Energy Phys.

2012-09-06T23:59:59.000Z

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


401

Predicting long-term lumen maintenance life of LED light sources using a particle filter-based prognostic approach  

Science Journals Connector (OSTI)

Abstract Lumen degradation is a common failure mode in LED light sources. Lumen maintenance life, defined as the time when the maintained percentages of the initial light output fall below a failure threshold, is a key characteristic for assessing the reliability of LED light sources. Owing to the long lifetime and high reliability of LED lights sources, it is challenging to estimate the lumen maintenance life for LED light sources using traditional life testing that records failure data. This paper describes a particle filter-based (PF-based) prognostic approach based on both Sequential Monte Carlo (SMC) and Bayesian techniques to predict the lumen maintenance life of LED light sources. The lumen maintenance degradation data collected from an accelerated degradation test was used to demonstrate the prediction algorithm and methodology of the proposed PF approach. Its feasibility and prediction accuracy were then validated and compared with the TM-21 standard method that was created by the Illuminating Engineering Society of North America (IESNA). Finally, a robustness study was also conducted to analyze the initialization of parameters impacting the prediction accuracy and the uncertainties of the proposed PF method. The results show that, compared to the TM-21 method, the PF approach achieves better prediction performance, with an error of less than 5% in predicting the long-term lumen maintenance life of LED light sources.

Jiajie Fan; Kam-Chuen Yung; Michael Pecht

2015-01-01T23:59:59.000Z

402

New Soft X-ray Beamline (BL10) at the SAGA Light Source  

SciTech Connect (OSTI)

A new soft X-ray beamline (BL10) at the SAGA Light Source (SAGA-LS) was constructed at the end of 2008. Commissioning of this new beamline started at the beginning of 2009. Synchrotron radiation from a variably polarizing undulator (APPLE-II) can be used in this beamline. The obtained light is monochromatized by a varied-line-spacing plane grating monochromator with the variable included angle mechanism. Its designed resolving power and photon flux are 3,000-10,000 and 10{sup 12}-10{sup 9} photons/s at 300 mA, respectively. The performance test results were generally satisfactory. An overview of the optical design of the beamline and the current status of commissioning are reported.

Yoshimura, D.; Setoyama, H.; Okajima, T. [Beamline group, SAGA Light Source, 8-7 Yayoigaoka, Tosu, Saga 841-0005 (Japan)

2010-06-23T23:59:59.000Z

403

Philips Light Sources & Electronics is Developing an Efficient, Smaller, Cost-Effective Family of LED Drivers  

Broader source: Energy.gov [DOE]

With the help of DOE funding, Philips Light Sources & Electronics is developing a new family of LED drivers that are more efficient and cost-effective as well as smaller in size than currently available drivers. The new drivers are switch-mode power supplies that are similar to today's drivers, but with an improved design. In addition, they have a different topologyboost plus LLCfor wattages of 40W and above, but they retain the commonly used flyback topology at lower wattages.

404

X-ray holographic microscopy experiments at the Brookhaven synchrotron light source  

SciTech Connect (OSTI)

Soft x-ray holographic microscopy is discussed from an experimental point of view. Three series of measurements have been carried out using the Brookhaven 750 MeV storage ring as an x-ray source. Young slits fringes, Gabor (in line) holograms and various data pertaining to the soft x-ray performance of photographic plates are reported. The measurements are discussed in terms of the technique for recording them and the experimental limitations in effect. Some discussion is also given of the issues involved in reconstruction using visible light.

Howells, M.R.; Iarocci, M.; Kenney, J.; Kirz, J.; Rarback, H.

1983-01-01T23:59:59.000Z

405

Successful Completion of the Top-off Upgrade of the Advanced Light Source  

SciTech Connect (OSTI)

An upgrade of the Advanced Light Source (ALS) to enable top-off operation has been completed during the last four years. The final work centered around radiation safety aspects, culminating in a systematic proof that top-off operation is equally safe as decaying beam operation. Commissioning and transition to full user operations happened in late 2008 and early 2009. Top-off operation at the ALS provides a very large increase in time-averaged brightness (by about a factor of 10) as well as improvements in beam stability. The following sections provide an overview of the radiation safety rationale, commissioning results, as well as experience in user operations.

Steier, C.; Bailey, B.; Baptiste, K.; Barry, W.; Biocca, A.; Byrne, W.; Casey, P.; Chin, M.; Donahue, R.; Duarte, R.; Fahmie, M.; Gath, B.; Jacobson, S.; Julian, J.; Jung, J. Y.; Kritscher, M.; Kwiatkowski, S.; Marks, S.; McKean, P.; Mueller, R. [LBNL, Berkeley, CA 94720 (United States)

2010-06-23T23:59:59.000Z

406

National synchrotron light source. Activity report, October 1, 1994--September 30, 1995  

SciTech Connect (OSTI)

This report discusses research conducted at the National Synchrotron Light Source in the following areas: atomic and molecular science; energy dispersive diffraction; lithography, microscopy, and tomography; nuclear physics; scattering and crystallography studies of biological materials; time resolved spectroscopy; UV photoemission and surface science; x-ray absorption spectroscopy; x-ray scattering and crystallography; x-ray topography; the 1995 NSLS annual users` meeting; 17th international free electron laser conference; micro bunches workshop; VUV machine; VUV storage ring parameters; beamline technical improvements; x-ray beamlines; x-ray storage ring parameters; the NSLS source development laboratory; the accelerator test facility (ATF); NSLS facility improvements; NSLS advisory committees; NSLS staff; VUV beamline guide; and x-ray beamline guide.

Rothman, E.Z.; Hastings, J. [eds.

1996-05-01T23:59:59.000Z

407

Optical design and performance of the inelastic scattering beamline at the National Synchrotron Light Source  

SciTech Connect (OSTI)

Phase I of the X21 beamline at the National Synchrotron Light Source was commissioned during 1993. The research program at the X21 beamline is focused on the study of electronic excitations in condensed matter with total energy resolution of 0.1 eV to 1.0 eV. The source is a 27 pole hybrid wiggler. A water-cooled horizontal focusing Si(220) monochromator and a spherically bent Si(444) analyzer were installed and commissioned. At 8 keV the energy resolution of the monochromator is about 0.7 eV, and the energy resolution of the analyzer is about 0.1 eV. Results from several selected experiments are also discussed.

Kao, C.C.; Siddons, D.P.; Oversluizen, T.; Hastings, J.B. [Brookhaven National Lab., Upton, NY (United States); Hamalainen, K. [Helsinki Univ. (Finland). Dept. of Physics; Krisch, M. [European Synchrotron Radiation Facility, 38 - Grenoble (France)

1994-12-31T23:59:59.000Z

408

National synchrotron light source annual report 1987: For the period of October 1, 1986--September 30, 1987  

SciTech Connect (OSTI)

This report contains the reports and operational information of the National Synchrotron Light source facility for 1987. The reports are grouped mainly under VUV research and x-ray research. (LSP)

White-DePace, S.; Gmur, N.F.; Thomlinson, W.

1987-10-01T23:59:59.000Z

409

Plasma studies on electron cyclotron resonance light ion source at CEA/Saclay  

SciTech Connect (OSTI)

By the 90s, the CEA has undertaken to develop the production of intense light ion beams from unconfined ECR plasma. Today, three sources for IPHI, SPIRAL2, and IFMIF projects (respectively, 100 mA of H{sup +}, 8 mA of D{sup +}, and 140 mA of D{sup +}) are installed at CEA/Saclay. In order to improve performances and decrease dimensions of these sources, it is necessary to better understand the mechanisms involved in the production and extraction of particles. As a consequence, theoretical and experimental studies are being carried out. We present a theoretical study based on SOLMAXP, a home-made particle-in-cell code. The aim is to investigate the possibility of reducing the plasma chamber size without loss of beam characteristics. This code has been validated by beam intensity measurements on a permanent magnet based source, producing a proton beam of 30 mA at 40 kV on the test bench BETSI. In order to reduce experimentally the dimensions of plasma chamber, a new source, named ALISES with variable plasma chamber volume, is under assembly.

Nyckees, S.; Delferriere, O.; Duperrier, R.; Harrault, F.; Tuske, O. [CEA/Saclay, DSM/IRFU/SACM/LEDA, F-91191-Gif/Yvette (France)

2012-02-15T23:59:59.000Z

410

Abstract 4138: Fluorescence laparoscopy with an LED light source enables fluorescence-guided resection of pancreatic cancer, labeled with fluorophore-conjugated antibodies, in mouse models.  

Science Journals Connector (OSTI)

...4138: Fluorescence laparoscopy with an LED light source enables fluorescence-guided...495-nm emission filter and a Stryker L9000 LED light source 24 hours after tail vein injection...Bouvet. Fluorescence laparoscopy with an LED light source enables fluorescence-guided...

Cristina A. Metildi; Sharmeela Kaushal; George A. Luiken; Mark A. Talamini; Robert M. Hoffman; Michael Bouvet

2013-04-15T23:59:59.000Z

411

Silicon nanocrystals as light sources: stable, efficient and fast photoluminescence with suitable passivation  

Science Journals Connector (OSTI)

Silicon optoelectronics is an emerging technological platform, which holds promise for providing better performance, mostly in terms of lower dissipation losses, than the traditional electronics. However, a monolithic integrated light source is still missing since bulk silicon is a very poor light emitter due to its indirect bandgap. The situation dramatically changes when the size of the crystal is reduced down into nanometric dimension (<5 nm), when efficient room-temperature luminescence of these tiny silicon nanocrystals sets in. In this contribution, we present a study of silicon nanocrystals as light sources. We compare the photoluminescence properties of silicon nanocrystals with three different types of surface passivation (hydrogen, silicon oxide and methyl-based capping), which has substantial impact. We show that with sufficiently small sizes and suitable surface passivation, the photoluminescence properties of silicon nanocrystals can reach a level comparable with direct-bandgap semiconductor nanocrystals (radiative lifetime of 10 ns, stable macroscopic quantum yield of 20%). Apart from studying photoluminescence properties on a macroscopic level, we also carried out microscopical room-temperature single-nanocrystal photoluminescence spectroscopy experiments. These spectra revealed the occurrence of a fine structure (peaks 150 meV apart), practically identical with a structure already observed in single-nanocrystal spectra of silicon by other groups and very similar to a structure observed in a fundamentally different type of semiconductor nanocrystals (IIVI material). We propose that all these observations are linked with the same process, most probably the emission of trions in nanocrystals, although further measurements are necessary to support this claim.

Kateř ina Ků sová

2012-01-01T23:59:59.000Z

412

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

E-Print Network [OSTI]

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

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

2014-01-01T23:59:59.000Z

413

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

E-Print Network [OSTI]

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

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

2014-01-23T23:59:59.000Z

414

Nuclear Charge Radii of Neutron-Deficient Lead Isotopes Beyond N=104 Midshell Investigated by In-Source Laser Spectroscopy  

Science Journals Connector (OSTI)

The shape of exotic even-mass Pb182190 isotopes was probed by measurement of optical isotope shifts providing mean square charge radii (??r2?). The experiment was carried out at the isolde (cern) on-line mass separator, using in-source laser spectroscopy. Small deviations from the spherical droplet model are observed, but when compared to model calculations, those are explained by high sensitivity of ??r2? to beyond mean-field correlations and small admixtures of intruder configurations in the ground state. The data support the predominantly spherical shape of the ground state of the proton-magic Z=82 lead isotopes near neutron midshell (N=104).

H. De Witte et al.

2007-03-16T23:59:59.000Z

415

The Spallation Neutron Source (SNS) project: a fertile ground for radiation protection and shielding challenges  

Science Journals Connector (OSTI)

......pulse intensity(18). A heavy water-cooled beryllium and...outer plug, which is a heavy water-cooled steel reflector...experience at modern research reactors, neutron beam lines at...International Conference on Advanced Monte Carlo for Radiation......

F. X. Gallmeier; P. D. Ferguson; I. I. Popova; E. B. Iverson

2005-12-20T23:59:59.000Z

416

Spin exchange optical pumping based polarized {sup 3}He filling station for the Hybrid Spectrometer at the Spallation Neutron Source  

SciTech Connect (OSTI)

The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60 Degree-Sign horizontal and 15 Degree-Sign vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized {sup 3}He filling station based on the spin exchange optical pumping method. It is designed to supply polarized {sup 3}He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the {sup 3}He pressure with respect to the scattered neutron energies. The depolarized {sup 3}He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.

Jiang, C. Y.; Tong, X.; Brown, D. R.; Culbertson, H.; Kadron, B.; Robertson, J. L. [Instrument and Source Design Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Graves-Brook, M. K. [Research Accelerator Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Hagen, M. E. [Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Lee, W. T. [Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234 (Australia); Winn, B. [Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2013-06-15T23:59:59.000Z

417

Neutron reflecting supermirror structure  

DOE Patents [OSTI]

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.

Wood, J.L.

1992-12-01T23:59:59.000Z

418

Neutron reflecting supermirror structure  

DOE Patents [OSTI]

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.

Wood, James L. (Drayton Plains, MI)

1992-01-01T23:59:59.000Z

419

From the neutron to three light neutrino species: Some highlights from sixty years of particle physics  

SciTech Connect (OSTI)

I consider the beginning to modern particle physics to be in 1932--33, when James Chadwick discovered the neutron at Cambridge, England, and Carl Anderson discovered the positron in Pasadena, California. I leave out the discoveries of the electron by J. J. Thomson, the nucleus and the proton by Ernest Rutherford, as well as the photon introduced by Albert Einstein and the neutrino as hypothesized by Wolfgang Pauli, as having occurred before my time.'' I was thus able to follow -- and sometimes participate in -- all the developments of modern particle physics. The story I will tell is as the unfolding of the field looked; to me -- an experimental particle physicists. As with Rashomon, this is as I see it. To get a different point of view, and no doubt there are many, you need different observer. One might ask, what did I know about physics in the 1930s, anyway It so happens that I did hear abut Chadwick's discovery at the time, mainly because my brother Maurice was working with him in 1934 on the photo-disintegration of the deuteron, and on the first good measurement of the neutron mass. I will concentrate on the thirty years, 1930 to 1960 which includes Dick Dalitz' important early contributions. I will then skip most of the next thirty years for lack of time, and end up with the study of the Z{sup 0} in e{sup +}e{sup {minus}} annihilation. For more details, and explicit references to published papers, I will refer the reader to a recent book by Robert Cahn and myself.

Goldhaber, G.

1990-07-01T23:59:59.000Z

420

New chicane magnet design for insertion device straights at the Advanced Light Source  

SciTech Connect (OSTI)

A chicane magnet incorporating counter-rotating permanent magnet pairs together with trim coils has been designed for use in the Advanced Light Source (ALS) straights in conjunction with two insertion devices. In particular, this design is being developed for use in the existing beam line (BL) 4 elliptically polarizing undulator (EPU) straight and in the BL11 EPU straight, currently under design and construction. The purpose of the chicane is to provide a fixed angular separation between two successive EPU photon fans, and to correct steering perturbations resulting from EPU polarization state changes. Polarization changes occur on the time scale of one second; associated steering corrections must be accomplished in less than a second. Hysteresis associated with conventional iron core electromagnets prevents fast steering correction to the required precision. This consideration motivated the iron-free design presented here.

Marks, Steve; Schlueter, Ross; Anderson, David; Gath, William; Jung, Jin-Young; Robin, David; Steier, Christoph; Stevens, Troy

2001-12-10T23:59:59.000Z

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


421

Comparison of the Electromagnetic Spectra of Common Light Sources: A General Chemistry Laboratory Exercise  

Science Journals Connector (OSTI)

Compact fluorescent light (CFL); light emitting diode (LED). ... White LED light can be produced by mixing light from red, green, and blue LEDs. ... Students observe that the white light from a six LED flashlight array (Figure 5) arises from two major peaks and that the spectrum is less continuous than those of incandescent bulbs, but more continuous than those of CFLs. ...

Edward Maslowsky, Jr.

2013-10-03T23:59:59.000Z

422

Use of light-emitting diodes as light sources to lower energy consumption for cultivation of photosynthesizing microorganisms  

Science Journals Connector (OSTI)

Experimental data are cited for the productivity of phototrophs subjected to interrupted illumination by light-emitting diodes. It is demonstrated that a significant reduction in energy consumption for the produc...

2011-03-01T23:59:59.000Z

423

Neutron source, linear-accelerator fuel enricher and regenerator and associated methods  

DOE Patents [OSTI]

A device for producing fissile material inside of fabricated nuclear elements so that they can be used to produce power in nuclear power reactors. Fuel elements, for example, of a LWR are placed in pressure tubes in a vessel surrounding a liquid lead-bismuth flowing columnar target. A linear-accelerator proton beam enters the side of the vessel and impinges on the dispersed liquid lead-bismuth columns and produces neutrons which radiate through the surrounding pressure tube assembly or blanket containing the nuclear fuel elements. These neutrons are absorbed by the natural fertile uranium-238 elements and are transformed to fissile plutonium-239. The fertile fuel is thus enriched in fissile material to a concentration whereby they can be used in power reactors. After use in the power reactors, dispensed depleted fuel elements can be reinserted into the pressure tubes surrounding the target and the nuclear fuel regenerated for further burning in the power reactor.

Steinberg, Meyer (Huntington Station, NY); Powell, James R. (Shoreham, NY); Takahashi, Hiroshi (Setauket, NY); Grand, Pierre (Blue Point, NY); Kouts, Herbert (Brookhaven, NY)

1982-01-01T23:59:59.000Z

424

Second and Third Harmonic Measurements at the Linac Coherent Light Source  

SciTech Connect (OSTI)

The Linac Coherent Light Source (LCLS) started user commissioning in October of 2009, producing Free Electron Laser (FEL) radiation between 800 eV and 8 keV [1]. The fundamental wavelength of the FEL dominates radiation in the beamlines, but the beam also produces nonnegligible levels of radiation at higher harmonics. The harmonics may be desirable as a source of harder X-rays, but may also contribute backgrounds to user experiments. In this paper we present preliminary measurements of the second and third harmonic content in the FEL. We also measure the photon energy cutoff of the soft X-ray mirrors to determine the extent to which higher harmonics reach the experimental stations. We present preliminary second and third harmonic measurements for LCLS. At low energies (below 1 keV fundamental) we measure less than 0.1% second harmonic content. The second harmonic will be present in the soft X-ray beam line for fundamental photon energies below approximately 1.1 keV. At low and high energies, we measure third harmonic content ranging from 0.5% to 3%, which is consistent with expectations. For both second and third harmonics, experimental work is ongoing. More rigorous analysis of the data will be completed soon.

Ratner, D.; /Stanford U., Phys. Dept.; Brachmann, A.; Decker, F.J.; Ding, Y.; Dowell, D.; Emma, P.; Fisher, A.; Frisch, J.; Gilevich, S.; Huang, Z.; Hering, P.; Iverson, R.; Krzywinski, J.; Loos, H.; Messerschmidt, M.; Nuhn, H.D.; Smith, T.; Turner, J.; Welch, J.; White, W.; Wu, J.; /SLAC

2011-01-03T23:59:59.000Z

425

The neutron identified: Sir James Chadwick  

Science Journals Connector (OSTI)

The neutron identified: Sir James Chadwick ... Uses source material to describe the discovery of the neutron by James Chadwick. ...

Alfred B. Garrett

1962-01-01T23:59:59.000Z

426

Assessing the Performance of 5mm White LED Light Sources for Developing-Country Applications  

E-Print Network [OSTI]

performance variations. Incandescent and fluorescent lightbetter than the common incandescent lamp. Off-grid lighting

Mills, Evan

2007-01-01T23:59:59.000Z

427

Palm top plasma focus device as a portable pulsed neutron source  

Science Journals Connector (OSTI)

Development of a palm top plasma focus device generating (5.2 0.8) 104 neutrons/pulse into 4? steradians with a pulse width of 15 3 ns is reported for the first time. The weight of the system is less than 1.5 kg. The system comprises a compact capacitor bank a triggered open air spark gap switch and a sealed type miniature plasma focus tube. The setup is around 14 cm in diameter and 12.5 cm in length. The energy driver for the unit is a capacitor bank of four cylindrical commercially available electrolytic capacitors. Each capacitor is of 2 ?F capacity 4.5 cm in diameter and 9.8 cm in length. The cost of each capacitor is less than US$ 10. The internal diameter and the effective length of the plasma focus unit are 2.9 cm and 5 cm respectively. A DC to DC converter power supply powered by two rechargeable batteries charges the capacitor bank to the desired voltage and also provides a trigger pulse of ?15 kV to the spark gap. The maximum energy of operation of the device is 100 J (8 ?F 5 kV 59 kA) with deuterium gas filling pressure of 3 mbar. The neutrons have also been produced at energy as low as 36 J (3 kV) of operation. The neutron diagnostics are carried out with a bank of 3He detectors and with a plastic scintillator detector. The device is portable reusable and can be operated for multiple shots with a single gas filling.

2013-01-01T23:59:59.000Z

428

Lighting  

SciTech Connect (OSTI)

The lighting section of ASHRAE standard 90.1 is discussed. It applies to all new buildings except low-rise residential, while excluding specialty lighting applications such as signage, art exhibits, theatrical productions, medical and dental tasks, and others. In addition, lighting for indoor plant growth is excluded if designed to operate only between 10 p.m. and 6 a.m. Lighting allowances for the interior of a building are determined by the use of the system performance path unless the space functions are not fully known, such as during the initial stages of design or for speculative buildings. In such cases, the prescriptive path is available. Lighting allowances for the exterior of all buildings are determined by a table of unit power allowances. A new addition the exterior lighting procedure is the inclusion of facade lighting. However, it is no longer possible to trade-off power allotted for the exterior with the interior of a building or vice versa. A significant change is the new emphasis on lighting controls.

McKay, H.N. (Hayden McKay Lighting Design, New York, NY (US))

1990-02-01T23:59:59.000Z

429

Operational characteristics of the J-PARC cryogenic hydrogen system for a spallation neutron source  

SciTech Connect (OSTI)

The J-PARC cryogenic hydrogen system provides supercritical hydrogen with the para-hydrogen concentration of more than 99 % and the temperature of less than 20 K to three moderators so as to provide cold pulsed neutron beams of a higher neutronic performance. Furthermore, the temperature fluctuation of the feed hydrogen stream is required to be within 0.25 K. A stable 300-kW proton beam operation has been carried out since November 2012. The para-hydrogen concentrations were measured during the cool-down process. It is confirmed that para-hydrogen always exists in the equilibrium concentration because of the installation of an ortho-para hydrogen convertor. Propagation characteristics of temperature fluctuation were measured by temporarily changing the heater power under off-beam condition to clarify the effects of a heater control for thermal compensation on the feed temperature fluctuation. The experimental data gave an allowable temperature fluctuation of 1.05 K. It is clarified through a 286-kW and a 524-kW proton beam operations that the heater control would be applicable for the 1-MW proton beam operation by extrapolating from the experimental data.

Tatsumoto, Hideki; Ohtsu, Kiichi; Aso, Tomokazu; Kawakami, Yoshihiko; Teshigawara, Makoto [J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195 (Japan)

2014-01-29T23:59:59.000Z

430

The 19th ICFA Advanced Beam Dynamics Workshop on Future Light Sources  

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

ICFA2000t.GIF (31362 bytes) ICFA2000t.GIF (31362 bytes) The 19th ICFA Advanced Beam Dynamics Workshop on Future Light Sources Physics of and Science with The X-ray Free-Electron Laser (Arcidosso, Italy, September 10-15, 2000) Workshop Summary The19th Advanced ICFA Beam Dynamics Workshop on "The Physics of, and the Science with, X-Ray Free-Electron Lasers" took place in Arcidosso (Italy) from the 10th to the 15th of September, 2000. The Workshop was sponsored by the International Committee for Future Accelerators, the US Department of Energy, the University of California at Los Angeles, the Stanford Linear Accelerator Center, the Deutsches Elektronen-Synchrotron and the Lawrence Berkeley National Laboratory, together with local authorities of the Tuscany, Grosseto and Arcidosso areas. The Workshop's chairmen were M. Cornacchia (SLAC), I. Lindau (SLAC/Lund. Un.) and C. Pellegrini (UCLA). Seventy-five scientists, of which 50 are involved in the physics and technology of accelerators, free-electron lasers and x-ray optics, and 25 in the scientific applications, attended the workshop. There were plenary and parallel sessions and many lively discussions, during and after the regular workshop schedule.

431

The U5. 0 undulator design for the advanced light source at LBL  

SciTech Connect (OSTI)

The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5 cm period, 5 m length with a 0.837 T maximum field at a 14 mm gap. A hybrid configuration utilizing Nd-Fe-B permanent magnet material and Vanadium Permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Vertical field integral correction at the ends is with permanent magnet rotators. The supports structure features a 4-post configuration, a rigid base with 3 kinematic floor supports and 2 rigid 5 m long backing beams that fit within the 2.4 m high accelerator enclosure. The drive system is computer controlled utilizing a stepper motor and shaft encode coupled to a roller-screw/nut and chain drive train. Vacuum chamber design is a rigid configuration with a 10 mm vertical by 218 mm horizontal aperture of 5.5 m length. Chamber fabrication features a two-piece welded chamber of 5083 H321 aluminum. Pumping is with ion and titanium sublimation pumps. 5 figs., 1 tab.

Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.; Savoy, R.

1989-08-01T23:59:59.000Z

432

Status of Cryogenic System for Spallation Neutron Source's Superconducting Radiofrequency Test Facility at Oak Ridge National Lab  

SciTech Connect (OSTI)

Spallation Neutron Source (SNS) at Oak Ridge National Lab (ORNL) is building an independent cryogenic system for its Superconducting Radiofrequency Test Facility (SRFTF). The scope of the system is to support the SNS cryomodule test and cavity test at 2-K (using vacuum pump) and 4.5K for the maintenance purpose and Power Upgrade Project of SNS, and to provide the part of the cooling power needed to backup the current CHL to keep Linac at 4.5-K during CHL maintenance period in the future. The system is constructed in multiple phases. The first phase is to construct an independent 4K helium refrigeration system with helium Dewar and distribution box as load interface. It is schedule to be commissioned in 2013. Here we report the concept design of the system and the status of the first phase of this project.

Xu, Ting [ORNL; Casagrande, Fabio [ORNL; Ganni, Venkatarao [ORNL; Knudsen, Peter N [ORNL; Strong, William Herb [ORNL

2011-01-01T23:59:59.000Z

433

Protein crystallography with spallation neutrons: the user facility at Los Alamos Neutron Science Center  

Science Journals Connector (OSTI)

The protein crystallography user facility at the neutron spallation source run by Los Alamos Neutron Science Center is described.

Langan, P.

2004-01-17T23:59:59.000Z

434

SciTech Connect: 2010 Neutron Review: ORNL Neutron Sciences Progress...  

Office of Scientific and Technical Information (OSTI)

117; GREENHOUSE GASES; HEAVY ION ACCELERATORS; HELIUM 3; HFIR REACTOR; IRON; JINR; MAGNETIC FIELDS; NEUTRON DETECTORS; NEUTRON SOURCES; NEUTRONS; ORNL; RELIABILITY;...

435

Near?fieldfar?field transition of a finite line source using incoherent light: A student laboratory experiment  

Science Journals Connector (OSTI)

A simple experiment employing low cost apparatus is presented which demonstrates the falloff of intensity with distance and the transition from the near field to the far field of a line source filament incandescent light bulb. A derivation of the Poynting vector as a function of the distance away from the filament is presented which shows an exact correspondence to the derivation for the electric field from a finite line charge source in electrostatics. The experimental data of power vs distance from the filament show an inverse first power of the distance falloff in the near field with a smooth transition to an inverse square law behavior in the far field in good agreement with the theoretical expression when corrections for the measured angular response of the detector are included. The experiment provides an illustration of the inverse square law falloff of intensity at large distances from the source experience with simple concepts and techniques of optical radiometry and incoherent light sources and the analogy between incoherent light sources and electrostatics in an undergraduate laboratory. An additional short experiment provides an illustration of electrical?to?optical power conversion efficiency and temperature dependent resistance associated with electronphonon scattering in metals. A derivation of isotropic unpolarized elementary radiators from anisotropic dipole radiation is presented in the Appendix.

Xincheng Yan; Yixin Yu; Louis Shen; Keith H. Wanser

1995-01-01T23:59:59.000Z

436

Neutron activation experiments in radiochemistry  

Science Journals Connector (OSTI)

Neutron activation experiments in radiochemistry ... Describes experimentation involving the neutron activation of a variety of samples irradiated in a subcritical reactor and a paraffin-moderated source. ...

Karl S. Vorres

1960-01-01T23:59:59.000Z

437

Characterization of the neutron source term and multiplicity of a spent fuel assembly in support of NSDA safeguards of spent nuclear fuel  

SciTech Connect (OSTI)

The gross neutron signal (GNS) is being considered as part of a fingerprinting or neutron balance approach to safeguards of spent nuclear fuel (SNF). Because the GNS is composed of many derivative components, understanding the time-dependent contribution of these derivative components is crucial to gauging the limitations of these approaches. The major components of the GNS are ({alpha}, n), spontaneous fission (SF), and multiplication neutrons. A methodology was developed to link MCNPX burnup output files to SOURCES4C input files for the purpose of automatically generating both the ({alpha}, n) and SF signals. Additional linking capabilities were developed to write MCNPX multiplication input files using the data obtained from the SOURCES4C output files. In this paper, the following are presented: (1) the relative contributions by source nuclide to the ({alpha}, n) signal as a function of initial enrichment/burnup/cooling time; (2) the relative contributions by source nuclide to the SF signal as a function of initial enrichment/burnup/cooling time; (3) the relative contributions by reaction type ({alpha},n vs. SF) to the GNS; and (4) the multiplication of the GNS as a function of initial enrichment/burnup/cooling time/counting environment. By developing these technologies to characterize the GNS, we can better evaluate the viability of the GNS fingerprint and neutron balance concepts for SNF.

Richard, Joshua G [Los Alamos National Laboratory; Fensin, Michael L [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Menlove, Howard O [Los Alamos National Laboratory; Baciak, James [UNIV OF FL.

2010-01-01T23:59:59.000Z

438

Lead-Bismuth-Eutectic Spallation Neutron Source for Nuclear Transmuter Y. Gohar, J. Herceg, L Krajtl, D. Pointer, J. Saiveau, T. Sofu, and P. Finck  

E-Print Network [OSTI]

-driven test facility (ADTF). The ADTF is a major nuclear research facility that will provide multiple testing to operate as a user facility that allows testing advanced nuclear technologies and applications, materialLead-Bismuth-Eutectic Spallation Neutron Source for Nuclear Transmuter Y. Gohar, J. Herceg, L

McDonald, Kirk

439

Thermal-hydraulic performance of a water-cooled tungsten-rod target for a spallation neutron source  

SciTech Connect (OSTI)

A thermal-hydraulic (T-H) analysis is conducted to determine the feasibility and limitations of a water-cooled tungsten-rod target at powers of 1 MW and above. The target evaluated has a 10-cm x 10-cm cross section perpendicular to the beam axis, which is typical of an experimental spallation neutron source - both for a short-pulse spallation source and long-pulse spallation source. This report describes the T-H model and assumptions that are used to evaluate the target. A 1-MW baseline target is examined, and the results indicate that this target should easily handle the T-H requirements. The possibility of operating at powers >1 MW is also examined. The T-H design is limited by the condition that the coolant does not boil (actual limits are on surface subcooling and wall heat flux); material temperature limits are not approached. Three possible methods of enhancing the target power capability are presented: reducing peak power density, altering pin dimensions, and improving coolant conditions (pressure and temperature). Based on simple calculations, it appears that this target concept should have little trouble reaching the 2-MW range (from a purely T-H standpoint), and possibly much higher powers. However, one must keep in mind that these conclusions are based solely on thermal-hydraulics. It is possible, and perhaps likely, that target performance could be limited by structural issues at higher powers, particularly for a short-pulse spallation source because of thermal shock issues.

Poston, D.I.

1997-08-01T23:59:59.000Z

440

Light emission of very low density hydrogen excited by an extremely hot light source; applications in astrophysics  

E-Print Network [OSTI]

Stromgren studied the action of an extremely hot source on a diluted pure hydrogen cloud; a very ionized, spherical hydrogen plasma surrounded by neutral atomic hydrogen is formed. A relatively thin intermediate, partially ionized, hydrogen shell, is cooled by the radiation of the atoms. Stromgren was unaware of that this plasma, similar to the plasma of a gas laser, can be superradiant at several eigen frequencies of atomic hydrogen; the superradiant rays emitted tangentially with the sphere appear resulting from a discontinuous ring because of the competition of optical modes. The superradiance intensely depopulates the excited levels, including the continuum of proton-electron collisions, by cascades of transitions combined into resonant multiphotonic transitions so that the gas is cooled brutally beyond the radius of the Stromgren sphere. The extreme brightness of the rays emitted by the source allows a multiphotonic non-resonant absorption leading in stationary states or the ionization continuum. This absorption combines with the superradiant emissions in a multiphotonic diffusion induced by the superradiant rays. Although its brightness remains higher than that of the superradiant rays, the source becomes invisible if it is observed through a small solid angle. The lines emitted inside the sphere are all the more weak as they arrive of an internal area, lower in atoms, and more reddened also by a parametric transfer of energy towards the thermal radiation catalyzed by excited atomic hydrogen present in the sphere only. The Stromgren sphere appears to help to simply explain the appearance and the spectrum of supernova 1987A.

Jacques Moret-Bailly

2008-07-19T23:59:59.000Z

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441

New neutron source aims to be top in energy and environmental stewardship  

SciTech Connect (OSTI)

Renewable, recyclable, responsible. That is the motto of the European Spallation Source (ESS). The ambitions to build the facility to be energetically self-sufficient and to have as small a carbon dioxide footprint as possible are, at least in part, what landed the project for Lund, Sweden, last year.

Feder, Toni [American Center for Physics, One Physics Ellipse, College Park, Maryland 20740-3842 (United States)

2010-03-15T23:59:59.000Z

442

Transmutation Performance Analysis for Inert Matrix Fuels in Light Water Reactors and Computational Neutronics Methods Capabilities at INL  

SciTech Connect (OSTI)

The urgency for addressing repository impacts has grown in the past few years as a result of Spent Nuclear Fuel (SNF) accumulation from commercial nuclear power plants. One path that has been explored by many is to eliminate the transuranic (TRU) inventory from the SNF, thus reducing the need for additional long term repository storage sites. One strategy for achieving this is to burn the separated TRU elements in the currently operating U.S. Light Water Reactor (LWR) fleet. Many studies have explored the viability of this strategy by loading a percentage of LWR cores with TRU in the form of either Mixed Oxide (MOX) fuels or Inert Matrix Fuels (IMF). A task was undertaken at INL to establish specific technical capabilities to perform neutronics analyses in order to further assess several key issues related to the viability of thermal recycling. The initial computational study reported here is focused on direct thermal recycling of IMF fuels in a heterogeneous Pressurized Water Reactor (PWR) bundle design containing Plutonium, Neptunium, Americium, and Curium (IMF-PuNpAmCm) in a multi-pass strategy using legacy 5 year cooled LWR SNF. In addition to this initial high-priority analysis, three other alternate analyses with different TRU vectors in IMF pins were performed. These analyses provide comparison of direct thermal recycling of PuNpAmCmCf, PuNpAm, PuNp, and Pu. The results of this infinite lattice assembly-wise study using SCALE 5.1 indicate that it may be feasible to recycle TRU in this manner using an otherwise typical PWR assembly without violating peaking factor limits.

Michael A. Pope; Samuel E. Bays; S. Piet; R. Ferrer; Mehdi Asgari; Benoit Forget

2009-05-01T23:59:59.000Z

443

Review of neutron calibration facilities and monitoring techniques: new needs for emerging fields  

Science Journals Connector (OSTI)

......Advancements in Nuclear Instrumentation...Proposal for an accelerator-based neutron...R. O. LANSCE nuclear science facilities...light-ion linear accelerator and neutron source...Imahori Y. In-situ vacuum deposition technique...the Birmingham Accelerator-Generated epIthermal......

V. Gressier

2014-10-01T23:59:59.000Z

444

Cold neutron research facility at the Budapest Neutron Centre  

Science Journals Connector (OSTI)

The new cold neutron research facility has been routinely operated at the Budapest Neutron Centre (BNC) since February 2001. This ... of equipment consists of a liquid hydrogen cold neutron source, an optimised s...

L. Rosta

2002-12-01T23:59:59.000Z

445

Structurally Integrated Photoluminescence-Based Lactate Sensor Using Organic Light Emitting Devices (OLEDs) as the Light Source  

SciTech Connect (OSTI)

Multianalyte bio(chemical) sensors are extensively researched for monitoring analytes in complex systems, such as blood serum. As a step towards developing such multianalyte sensors, we studied a novel, structurally integrated, organic light emitting device (OLED)-based sensing platform for detection of lactate. Lactate biosensors have attracted numerous research efforts, due to their wide applications in clinical diagnosis, athletic training and food industry. The OLED-based sensor is based on monitoring the oxidation reaction of lactate, which is catalyzed by the lactate oxidase (LOX) enzyme. The sensing component is based on an oxygen-sensitive dye, Platinum octaethyl porphyrin (PtOEP), whose photoluminescence (PL) lifetime {tau} decreases as the oxygen level increases. The PtOEP dye was embedded in a thin film polystyrene (PS) matrix; the LOX was dissolved in solution or immobilized in a sol-gel matrix. {tau} was measured as a function of the lactate concentration; as the lactate concentration increases, {tau} increases due to increased oxygen consumption. The sensors performance is discussed in terms of the detection sensitivity, dynamic range, and response time. A response time of {approx}32 sec was achieved when the LOX was dissolved in solution and kept in a closed cell. Steps towards development of a multianalyte sensor array using an array of individually addressable OLED pixels were also presented.

Chengliang Qian

2006-08-09T23:59:59.000Z

446

Breakthroughs in Practical-Sized, High Quality OLED Light Panel Source  

Broader source: Energy.gov [DOE]

General Electric Global Research has achieved a major breakthrough, developing a fully functional 2 ft. x 2 ft. light panel that produces more than 1200 lumens of quality white light with an efficacy of 15 lumens per watt. This device offers 50% better energy performance than their previous device, breaking two world records.

447

Neutron Scattering Facilities | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Neutron Scattering Facilities Neutron Scattering Facilities Scientific User Facilities (SUF) Division SUF Home About User Facilities X-Ray Light Sources Neutron Scattering Facilities Nanoscale Science Research Centers Electron-Beam Microcharacterization Centers Accelerator & Detector Research & Development Principal Investigators' Meetings Scientific Highlights Construction Projects BES Home User Facilities Neutron Scattering Facilities Print Text Size: A A A RSS Feeds FeedbackShare Page This activity supports the operation of three DOE neutron scattering facilities, which are unique and effective tools for probing the structure of matter. Neutron scattering is particularly well-suited for determining the atomic positions of both light and heavy atoms in a solid and thermal fluctuations in these positions. In addition the neutron

448

X-RAY ACTIVE MATRIX PIXEL SENSORS BASEDON J-FET TECHNOLOGY DEVELOPED FOR THE LINAC COHERENT LIGHT SOURCE.  

SciTech Connect (OSTI)

An X-ray Active Matrix Pixel Sensor (XAMPS) is being developed for recording data for the X-ray Pump Probe experiment at the Linac Coherent Light Source (LCLS). Special attention has to be paid to some technological challenges that this design presents. New processes were developed and refined to address problems encountered during previous productions of XAMPS. The development of these critical steps and corresponding tests results are reported here.

CARINI,G.A.; CHEN, W.; LI, Z.; REHAK, P.; SIDDONS, D.P.

2007-10-29T23:59:59.000Z

449

Energy efficiency and color quality limits in artificial light sources emulating natural illumination  

Science Journals Connector (OSTI)

We present in this work a calculation of the theoretical limits attainable for natural light emulation with regard to the joint optimization of the Luminous Efficacy of Radiation and...

Hertog, Wim; Llenas, Aleix; Quintero, Jess M; Hunt, Charles E; Carreras, Josep

2014-01-01T23:59:59.000Z

450

On the Doppler effect for light from orbiting sources in Kerr-type metrics  

E-Print Network [OSTI]

A formula is derived for the combined motional and gravitational Doppler effect in general stationary axisymmetric metrics for a photon emitted parallel or antiparallel to the assumed circular orbital motion of its source. The same formula is derived from eikonal approximation and Killing vector approaches to elucidate connections between observational astronomy and modern Relativity. The formula yields expected results in the limits of a moving or stationary source in the exterior Kerr and Schwarzschild metrics and a moving source in flat space.

S. Cisneros; G. Goedecke; C. Beetle; M. Engelhardt

2012-03-12T23:59:59.000Z

451

Conceptual design of thorium-fuelled Mitrailleuse accelerator-driven subcritical reactor using D-Be neutron source  

SciTech Connect (OSTI)

A distributed accelerator is a charged-particle accelerator that uses a new acceleration method based on repeated electrostatic acceleration. This method offers outstanding benefits not possible with the conventional radio-frequency acceleration method, including: (1) high acceleration efficiency, (2) large acceleration current, and (3) lower failure rate made possible by a fully solid-state acceleration field generation circuit. A 'Mitrailleuse Accelerator' is a product we have conceived to optimize this distributed accelerator technology for use with a high-strength neutron source. We have completed the conceptual design of a Mitrailleuse Accelerator and of a thorium-fuelled subcritical reactor driven by a Mitrailleuse Accelerator. This paper presents the conceptual design details and approach to implementing the subcritical reactor core. We will spend the next year or so on detailed design work, and then will start work on developing a prototype for demonstration. If there are no obstacles in setting up a development organization, we expect to finish verifying the prototype's performance by the third quarter of 2015. (authors)

Kokubo, Y. [Quan Japan Company Limited, 3-9-15 Sannomiya-cho, Chuo-ku, Kobe, Hyogo, 650-0021 (Japan); Kamei, T. [Research Inst. for Applied Sciences, 49 Tanaka Ohicho, Sakyo-ku, Kyoto-shi, Kyoto, 606-8202 (Japan)

2012-07-01T23:59:59.000Z

452

Design, production, and evaluation of a zircaloy-clad uranium target for an intense pulsed neutron source application  

SciTech Connect (OSTI)

The design of a Zircaloy-2-clad uranium alloy (450 ppm carbon, 250 ppm iron, 350 ppm silicon) target that can function as a pulsed spallation neutron source on interaction of a pulsed 500-MeV proton beam with the uranium nuclei is determined by consideration of irradiation damage, energy deposition, and thermal cycling effects in the target. The designed target is comprised of eight watercooled Zircaloy-2-clad uranium alloy disks, 10 cm in diameter and 2.7 cm thick operating at a maximum uranium alloy centerline temperature of 330/sup 0/C. The production of the Zircaloy-2-clad uranium alloy disks involves remelting of the cast uranium alloy by the consumable electrode technique and bonding of the Zircaloy-2 to the uranium alloy by subjecting the composite to an isostatic-helium pressure at 840/sup 0/C. The lifetime of the disks in the target before cracking of the Zircaloy-2 cladding owing to lowfrequency thermal cycling fatigue is estimated from stress calculations to be about 500 days. The results of thermal cycling tests on a disk tend to confirm the results of the stress calculations.

Loomis, B.A.; Fogle, G.L.; Gerber, S.B.; Thresh, H.R.

1981-12-01T23:59:59.000Z

453

Pinpointing extragalactic neutrino sources in light of recent IceCube observations  

Science Journals Connector (OSTI)

The IceCube Collaboration has recently reported the observation of a flux of high-energy astrophysical neutrinos. The angular distribution of events is consistent with an isotropic arrival direction of neutrinos which is expected for an extragalactic origin. We estimate the prospects of detecting individual neutrino sources from a quasidiffuse superposition of many extragalactic sources at the level of the IceCube observation. Unlike previous analyses, we take into account ensemble variations of the source distribution as well as the event statistics of individual sources. We show that IceCube in its present configuration is sensitive to rare ?10?8??Mpc?3