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''Magic'' Energies for Detecting Light Elements with Resonant Alpha Particle Backscattering

Description: Resonant backscattering is widely used to improve the detection limit of the light elements such as B, C, N and O. One disadvantage, however, is that several incident energies are normally needed if the sample contains a number of the light elements. There are ''magic'' energies at which several light elements can be detected simultaneously with suitable sensitivities. When these energies are used along with the elastic recoil detection of hydrogen, multiple elements can be detected without cha… more
Date: November 4, 1998
Creator: Wetteland, C.J.; Maggiore, C.J.; Tesmer, J.R.; He, X-M. & Lee, D-H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Carrier-free Radioisotopes from Cyclotron Targets I. Preparation and Isolation of Sn113 and In114 from Cadmium

Description: The cyclotron is the only practical source of many carrier-free radioisotopes. The preparation and radiochemical isolation of a number of these activities, produced in the 60-inch cyclotron of Crocker Laboratory, will be presented in this paper and in subsequent papers of this series. In most cases the carrier-free radioisotopes were prepared for use in biological systems and the final preparations were in the form of isotonic saline solutions at a range of pH from 5 to 8. The present paper rep… more
Date: August 11, 1949
Creator: Maxwell, R. D.; Haymond, H. R.; Bobmberger, D. R.; Garrison, W. M. & Hamilton, J. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Fission of Thorium with Alpha Particles

Description: The fission distribution of fission of thorium with alpha particle of average energy 37.5 Mev has been measured by the chemical method. The distribution found shows that the characteristic dip in the fission yield mass spectrum has been raised to within a factor of two of the peaks compared to a factor of 600 in slow neutron fission of U{sup 235}. The raise in the deip has caused a corresponding lowering in fission yield of these elements at the peaks. The cross section for fission of thorium w… more
Date: April 15, 1948
Creator: Newton, Amos S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Production of Mesons by the 184-inch Berkeley Cyclotron

Description: The authors have observed tracks which they believe to be due to mesons in photographic plates placed near a target bombarded by 380 Mev alpha particles. For a 10-minute exposure in the cyclotron, about 50 meson tracks are found along the 3-inch edge of a photographic plate. The mass has been determined by measuring the bending in the magnetic field and the range in emulsion. From the first 50 meson tracks measured they find a mass of 313 {+-} 16 electron masses. It is highly probable that thes… more
Date: January 1, 1948
Creator: Gardner, Eugene & Lattes, C. M. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Alpha-particle Measurements Needed for Burning Plasma Experiments

Description: The next major step in magnetic fusion studies will be the construction of a burning plasma (BP) experiment where the goals will be to achieve and understand the plasma behavior with the internal heating provided by fusion-generated alpha particles. Two devices with these physics goals have been proposed: the International Thermonuclear Experimental Reactor (ITER) and the Fusion Ignition Research Experiment (FIRE). Extensive conceptual design work for the instrumentation to try to meet the phys… more
Date: September 26, 2001
Creator: Young, Kenneth M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AN IMPROVED NUCLEAR DENSITY GAUGE. Period covered: September 2 to October 1, 1959

Description: Progress in development of a nuclear density gage for use in thickness and density measurements is reported. A Ross filter system for energy discrimination in the alpha ray region was constructed. Soller slits for collimating the radiation entering and leaving the filters so that a constant absorber thickness is seen by the radiation beam is under construction. Comments by visiting Russian scientists on the density gage and a discussion of their work in this area are included. (J.R.D.)
Date: October 31, 1960
Creator: Burgwald, G.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tank 241-AN-105, cores 152 and 153, analytical results for the 45 day report

Description: This document is the 45-day laboratory report for tank 241-AN-105 push mode core segments collected between June 10, 1996 and June 28, 1996. The segments were subsampled and analyzed in accordance with the Tank 241-AN-105 Push Mode Core Sampling and analysis Plan (TSAP) and the Safety Screening Data Quality Objective (DQO). The analytical results are included in the data summary table. None of the samples submitted for Total Alpha Activity or Differential Scanning Calorimetry (DSC) analyses exc… more
Date: September 20, 1996
Creator: Steen, F. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of energetic confined alphas and tritons on TFTR

Description: In a collaboration involving General Atomics, the A. F. Ioffe Physical-Technical Institute, and the Princeton Plasma Physics Laboratory, the energy distribution of the fast-confined alpha particles in DT experiments on TFIR is being measured by active neutral particle analysis using the ablation cloud surrounding an injected impurity pellet as the neutralizer. Recent papers reported the first measurements of the energy distribution fast confined alpha particles and examined the influence of mag… more
Date: August 1, 1995
Creator: Medley, S. S.; Duong, H. H. & McChesney, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cosmic Ray Produced Ar37 and Ar39 Activities in Recently Fallen Meteorites

Description: Several methods of determining meteorite ages depend ages upon nuclides formed by cosmic ray interactions. The tactic assumption is always made that the intensity of cosmic radiation does not vary in time or space. However it is known that the intensity of cosmic radiation at the earth varies with the solar activity. The spectrum of cosmic ray protons and alpha particles exhibit a marked drop at the low energy end (<1.5 GeV) and the intensity in the region appears to follow the 11 year cycle of… more
Date: February 1, 1968
Creator: Davis, R. Jr.; Stoenner, R. W. & Schaeffer, O. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Results Obtained From the Fricke Diffusion Kinetics Code

Description: The Diffusion Kinetics codes described previously in ANL-6556 were used to study hypothetical reactions of free radicals produced by passing alpha rays and gamma rays through aqueous solutions. Tables and graphs of results are given for about 200 cases run on the IBM 704 with various parameter combinations. Intermediate as well as final concentrations are given for some gamma -ray cases. (auth)
Date: September 1, 1962
Creator: Bareiss, E.H.; Chamot, C. & Fricke, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Anomalous loss of DT alpha particles in the Tokamak Fusion Test Reactor

Description: An escaping alpha collector probe has been developed for TFTR`s DT phase. Energy distributions of escaping alphas have been determined by measuring the range of {alpha}-particles implanted into nickel foils located within the alpha collector. Results at 1.0 MA of plasma current are in good agreement with predictions for first orbit alpha loss. Results at 1.8 MA, however, show a significant anomalous loss of partially thermalized alphas (in addition to the expected first orbit loss), which is no… more
Date: September 1, 1997
Creator: Herrmann, H.W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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MHD-Induced Alpha Particle Loss in TFTR

Description: MHD-induced increases in alpha particle loss to the wall were observed for both coherent modes and transient reconnection events using an array of scintillator detectors near the wall of Tokamak Fusion Test Reactor (TFTR). The magnitude of the coherent MHD-induced alpha loss as seen by these detectors was normally comparable to the MHD-quiescent first-orbit or toroidal-field ripple loss, but the magnitude of the alpha loss during reconnection events was up to 1000 times higher than this for a s… more
Date: March 1, 1999
Creator: Darrow, D. S.; Fredrickson, E. D.; Taylor, G.; White, R. B.; Zweben, S. J. & Von Goeler, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha contamination assessment for D&D activities: Monitoring concrete surfaces

Description: The process of decontaminating and decomissioning former nuclear facilities sometimes requires that large areas of concrete and other materials be scanned to verify they are not contaminated. A specially developed concrete surface monitor (CSM) can greatly expedite that process. The CSM is basically an aluminum box, open on the bottom, that uses an electrostatic field to transport ions created by alpha particles interacting with ambient air to a collection grid or plate. A sensitive electromete… more
Date: February 1, 1996
Creator: Rawool-Sullivan, M.W.; Conaway, J.G. & MacArthur, D.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Problems Found Using a Radon Stripping Algorithm for Retrospective Assessment of Air Filter Samples

Description: An evaluation of a large number of air sample filters was undertaken using a commercial alpha and beta spectroscopy system employing a passive implanted planar silicon (PIPS) detector. Samples were only measured after air flow through the filters had ceased. Use of a commercial radon stripping algorithm was implemented to discriminate anthropogenic alpha activity on the filters from the radon progeny. When uncontaminated air filters were evaluated, the results showed that there was a time-depen… more
Date: April 1, 2008
Creator: Hayes, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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