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Fission Detection Using the Associated Particle Technique

Description: A beam of tagged 14 MeV neutrons from the deuterium-tritium (DT) reaction is used to induce fission in a target composed of depleted uranium. The generator yield is 107 neutrons/second radiated into a 4π solid angle. Two 4 in.×4 in. NaI detectors are used for gamma-ray detection. The fission process is known to produce multiple gamma-rays and neutrons. Triple coincidences (α-γ-γ) are measured as a function of neutron flight time up to 90 ns after fission, where the α-particle arises from the DT… more
Date: September 18, 2008
Creator: R.P. Keegan, J.P. Hurley, J.R. Tinsley, R. Trainham, S.C. Wilde
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Aerial Neutron Detection of Cosmic-Ray Interactions with the Earth's Surface

Description: We have demonstrated the ability to measure the neutron flux produced by the cosmic-ray interaction with nuclei in the ground surface using aerial neutron detection. High energy cosmic-rays (primarily muons with GeV energies) interact with the nuclei in the ground surface and produce energetic neutrons via spallation. At the air-surface interface, the neutrons produced by spallation will either scatter within the surface material, become thermalized and reabsorbed, or be emitted into the air. T… more
Date: September 18, 2008
Creator: Maurer, Richard
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Can Handheld Plastic Detectors Do Both Gamma and Neutron Isotopic Identification with Directional Source Location?

Description: 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… more
Date: April 18, 2008
Creator: Hayes, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Possible error-prone repair of neoplastic transformation induced by fission-spectrum neutrons

Description: We have examined the effect of fission-spectrum neutrons from the JANUS reactor at Argonne National Laboratory, delivered either as acute or protracted irradiation, on the incidence of neoplastic transformation in the C3H 1OT1/2 mouse embryo cell line. Acute exposures were delivered at 10 to 38 rads/min, protracted exposures at 0.086 or 0.43 rad/min. The total doses for both ranged from 2.4 to 350 rads. In the low dose region (2.4 to 80 rads), there was a large enhancement in transformation fre… more
Date: July 18, 1983
Creator: Hill, C. K.; Han, A. & Elkind, M. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fast Neutron Interactions with Li⁶ and Li⁷

Description: Abstract: "Measurements have been made of the cross sections for the reactions Id-6(n, dn)He-4 and Li-7(n, tn)He-4 over an incident neutron energy range of 5 - 14 MeV. The energy and angular distributions of all reaction products were determined."
Date: July 18, 1963
Creator: Rosen, Louis
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-Energy X-Ray Imager for Laser-Fusion Research at the National Ignition Facility

Description: X-ray imaging will be an important diagnostic tool for inertial confinement fusion (ICF) research at the National Ignition Facility (NIF). However, high neutron yields will make x-ray imaging much more difficult than it is at smaller facilities. We analyze the feasibility and performance of a High-Energy X-Ray Imager (HEXRI) to be used on cryogenic DT implosions at NIF, with particular emphasis on spatial-resolution, field of view, signal-to-background and signal-to-noise ratios. Using a pinhol… more
Date: April 18, 2005
Creator: Tommasini, R & Koch, J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Very high-spin states in nuclei. [. gamma. spectra]

Description: The continuum ..gamma..-ray spectrum following neutron emission in a (HI,xn) reaction consists of a high-energy tail, the statistical cascade, and a lower-energy bump, the yrast cascade, which contains most of the intensity and consists mostly of stretched E2 transitions. Thus, a good approximation to the average angular momentum carried by the ..gamma..-rays is 2N/sub ..gamma../-bar. Under favourable conditions, effective moments of inertia can be deduced for states up to the top of the ..gamm… more
Date: April 18, 1977
Creator: Diamond, R. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proof-of-Principle Measurements on Unirradiated Zirconium Alloys

Description: The ability to determine fuel assembly burnup has important non-proliferation implications since proliferation activities involve either irradiating fuel assemblies to a much lower level of burnup than is normal in commercial Light Water Reactor (LWR) practice, and/or irradiation of separate targets. Similarly, a method of determining burnup could be used to confirm declared operation for a reactor that is operating under IAEA safeguards. It is possible to determine fuel assembly burnup by meas… more
Date: April 18, 2007
Creator: Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J. & Hurley, David E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha Heating in ITER L-mode and H-mode Plasma

Description: There are many uses of predictions of ITER plasma performance. One is assessing requirements of different plasma regimes. For instance, what current drive and control are needed for steady state. The heating, current drive, and torque systems planned for initial DT operation are negative ion neutral beam injection (NB), ion cyclotron resonance (IC), and electron cyclotron resonance (EC). Which combinations of heating are optimal. What are benefits of the torques, current drive, and fueling usin… more
Date: July 18, 2011
Creator: Budny, R.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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EFFECTS OF NITRIC ACID ON CRITICALITY SAFETY ANALYSIS

Description: As nitric acid molarity is increased, there are two competing phenomena affecting the reactivity of the system. First, there is interaction between each of the 10 wells in the basket-like insert. As the molarity of the nitric acid solution is increased (it moves from 100% water to 100% HNO{sub 3}), the hydrogen atom density decreases by about 80%. However, it remains a relatively efficient moderator. The moderating ratio of nitric acid is about 90% that of water. As the media between the wells … more
Date: August 18, 2011
Creator: Williamson, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phil Wallace and Theoretical Physics at McGill in the 1950's: A Personal Perspective

Description: In 1946 Philip (Phil) Russell Wallace joined the Mathematics Department of McGill University as an Associate Professor of Applied Mathematics, apparently because A. H. S. Gillson, Dean of Arts and Science, wanted theoretical physicists to be in the Mathematics Department. He came with the dream of creating a theoretical physics group at McGill. By the spring of 1949, Phil was authorized to recruit two junior faculty in Mathematics. He hired Theodore (Ted) F. Morris from U. Toronto, who joined i… more
Date: November 18, 2010
Creator: Jackson, John David
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multiscale Modeling of the Deformation of Advanced Ferritic Steels for Generation IV Nuclear Energy

Description: The objective of this project is to use the multi-scale modeling of materials (MMM) approach to develop an improved understanding of the effects of neutron irradiation on the mechanical properties of high-temperature structural materials that are being developed or proposed for Gen IV applications. In particular, the research focuses on advanced ferritic/ martensitic steels to enable operation up to 650-700°C, compared to the current 550°C limit on high-temperature steels.
Date: April 18, 2009
Creator: Ghoniem, Nasr M. & Kioussis, Nick
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Summary of the Research Progress Meeting

Description: This summary of the research progress meeting on March 18, 1948 covers the following topics: (1) Proton-proton scattering at 7 Mev; (2) Some animal experiments with 90 Mev neutrons; and (3) Yields of spallation products of antimony.
Date: March 18, 1948
Creator: Folden, M.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Compact neutron generator developement and applications

Description: The Plasma and Ion Source Technology Group at the Lawrence Berkeley National Laboratory has been engaging in the development of high yield compact neutron generators for the last ten years. Because neutrons in these generators are formed by using either D-D, T-T or D-T fusion reaction, one can produce either mono-energetic (2.4 MeV or 14 MeV) or white neutrons. All the neutron generators being developed by our group utilize 13.5 MHz RF induction discharge to produce a pure deuterium or a mixtur… more
Date: January 18, 2004
Creator: Leung, Ka-Ngo; Reijonen, Jani; Gicquel, Frederic; Hahto, Sami & Lou, Tak-Pui
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling Efforts to Aid in the Determination of Process Enrichment Levels for Identifying Potential Material Diversion

Description: Efforts have been under way at Lawrence Livermore National Laboratory (LLNL) to develop detailed analytical models that simulate enrichment and conversion facilities for the purpose of aiding in the detection of material diversion as part of an overall safeguards strategy. These models could be used to confirm proper accountability of the nuclear materials at facilities worldwide. Operation of an enrichment process for manufacturing commercial reactor fuel presents proliferation concerns includ… more
Date: January 18, 2006
Creator: Guenther, C F; Elayat, H A & O'Connell, W J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Impact Of Lithium Wall Coatings On NSTX Discharges And The Engineering Of The Lithium Tokamak eXperiment (LTX)

Description: Recent experiments on the National Spherical Torus eXperiment (NSTX) have shown the benefits of solid lithium coatings on carbon PFC's to diverted plasma performance, in both Land H- mode confinement regimes. Better particle control, with decreased inductive flux consumption, and increased electron temperature, ion temperature, energy confinement time, and DD neutron rate were observed. Successive increases in lithium coverage resulted in the complete suppression of ELM activity in H-mode disch… more
Date: March 18, 2010
Creator: Majeski, R.; Kugel, H. & Kaita, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SHIELDING-RESEARCH AREA AT BATTELLE

Description: The design and constructlon of the shielding facility at Battelle are described. This facility consists of an open pool with a fission plate, an instrument bridge and tower, a control room, and radiation-detection instruments. The shielding pool is located at the end of the thermal column of the Battelle Research Reactor (BRR). The fission plate is 28 in. in diameter and contains approximately 3.5 kg of U/sup 235/. The plate was fabricated from three pieces of highly enriched U and clad with ab… more
Date: September 18, 1958
Creator: Morgan, W.R.; Epstein, H.M.; Anno, J.N. Jr. & Chastain, J.W. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Production and Decay of the K<Sup>0</Sup> Meson

Description: This paper was previously abstracted irom the original language and appears in NSA Vol. 11, as abstract No. 13429. l9565 Selection rules, which occur ln the annihilation of a found nueleon-antinucleon system were examined. The decay of neutral K mesons with allowance for the conservation of combined parity was also investigated. (auth)
Date: May 18, 1959
Creator: Parker, Sherwood
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Fission Spectrum

Description: Measurements of the spectrum of the fission neutrons of 25 are described, in which the energy of the neutrons is determined from the ionization produced by individual hydrogen recoils. The slow neutrons producing fission are obtained by slowing down the fast neutrons from the Be-D reaction of the Stanford cyclotron. In order to distinguish between fission neutrons and the remaining fast cyclotron neutrons both the cyclotron current and the pusle amplifier are modulated. A hollow neutron contain… more
Date: August 18, 1943
Creator: Bloch, F. & Staub, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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