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Report to the DOE Nuclear Data Committee, 1984

Description: Experimental results are discussed for: /sup 6/ /sup 7/Li(n,/sup 4/He) cross sections at 14 MeV, neutron elastic and inelastic scattering from carbon near 14 MeV, neutron capture cross sections for /sup 46/Ca and /sup 48/Ca at stellar temperatures, revised neutron cross sections for /sup 142/ /sup 143/ /sup 144/Nd, fragment angular distribution for neutron fission of /sup 232/Th, neutron differential scattering measurements in the actinide region, nuclear structure of /sup 244/Am, conversion co… more
Date: February 1, 1984
Creator: Wong, C.; Haight, R. C. & Struble, G. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron scattering cross sections for /sup 232/Th and /sup 238/U inferred from proton scattering and charge exchange measurements. [7 MeV, 26 and 27 MeV]

Description: Differential cross sections for the (p,n) reactions to the isobaric analog states (IAS) of /sup 232/Th and /sup 238/U targets were measured at 26 and 27 MeV. The analysis of the data was done in conjunction with the proton elastic and inelastic (2/sup +/, 4/sup +/, 6/sup +/) differential cross sections measured at 26 MeV. Because collective effects are important in this mass region, deformed coupled-channels calculations were carried out for the simultaneous analysis of the proton and neutron o… more
Date: January 1, 1980
Creator: Hansen, L. F.; Grimes, S. M.; Pohl, B. A.; Poppe, C. H. & Wong, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DiMES Studies of Temperature Dependence of Carbon Erosion and Re-Deposition in the DIII-D Divertor

Description: A strong effect of a moderately elevated surface temperature on net carbon deposition and deuterium co-deposition in the DIII-D divertor was observed under detached conditions. A DiMES sample with a gap 2 mm wide and 18 mm deep was exposed to lower-single-null (LSN) L-mode plasmas first at room temperature, and then at 200 C. At the elevated temperature, deuterium co-deposition in the gap was reduced by an order of magnitude. At the plasma-facing surface of the heated sample net carbon erosion … more
Date: October 2, 2006
Creator: Rudakov, D.; Jacob, W.; Krieger, K.; Litnovsky, A.; Philipps, V.; West, W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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First Wall and Operational Diagnostics

Description: In this chapter we review numerous diagnostics capable of measurements at or near the first wall, many of which contribute information useful for safe operation of a tokamak. There are sections discussing infrared cameras, visible and VUV cameras, pressure gauges and RGAs, Langmuir probes, thermocouples, and erosion and deposition measurements by insertable probes and quartz microbalance. Also discussed are dust measurements by electrostatic detectors, laser scattering, visible and IR cameras, … more
Date: June 19, 2006
Creator: Lasnier, C.; Allen, S.; Boedo, J.; Groth, M.; Brooks, N.; McLean, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Migration of Artificially Introduced Micron Size Carbon Dust in the DIII-D Divertor

Description: Migration of pre-characterized carbon dust in a tokamak environment was studied by introducing about 30 milligrams of dust flakes 5-10 {micro}m in diameter in the lower divertor of DIII-D using the DiMES sample holder. The dust was exposed to high power ELMing Hmode discharges in lower-single-null magnetic configuration with the strike points swept across the divertor floor. When the outer strike point (OSP) passed over the dust holder exposing it to high particle and heat fluxes, part of the d… more
Date: May 15, 2006
Creator: Rudakov, D.; West, W.; Wong, C.; Brooks, N.; Evans, T.; Fenstermacher, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dust Measurements in Tokamaks

Description: Dust production and accumulation impose safety and operational concerns for ITER. Diagnostics to monitor dust levels in the plasma as well as in-vessel dust inventory are currently being tested in a few tokamaks. Dust accumulation in ITER is likely to occur in hidden areas, e.g. between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In DIII-D tokamak dust diagnostics include Mie scattering from Nd… more
Date: April 23, 2008
Creator: Rudakov, D.; Yu, J.; Boedo, J.; Hollmann, E.; Krasheninnikov, S.; Moyer, R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Assessment of problems associated with tritium containment

Description: Preventing tritium leakage across a large heat transfer area at high temperature is one of the most difficult problems associated with a D-T fusion reactor design. One of the most efficient methods to reduce the mobility of tritium is to convert it to tritiated water. Most solid breeder systems use a purge gas and assume tritium will be oxidized into the water form. For 17 Li-83Pb system, a double-walled steam generator is used. Tritium is assumed to be oxidized across the gap in between the tw… more
Date: January 1, 1984
Creator: Sze, D.K.; Hassanein, A.; Piet, S.; Wong, C. & Bjorndahl, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neutron spectra from materials used in fusion and fusion--fission hybrid reactors

Description: The neutron leakage spectra from pulsed spheres of Cu (1.0, 3.0, and 5.0 mean-free-path, mfp), Nb (1.0 and 3.0 mfp), /sup 232/Th (1.0 mfp) and /sup 238/U (0.8 and 2.8 mfp) have been measured using time-of-flight techniques. The neutron spectra from the above materials used in fusion hybrid reactors have been measured between 0.8 and 14 MeV using a stilbene scintillator, pulse shape discrimination and flight paths of around 10 meters. The measured spectra are compared with calculations carried o… more
Date: September 1, 1978
Creator: Hansen, L. F.; Wong, C.; Komoto, T. & Pohl, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neutron flux measurement at RTNS facility

Description: Procedures and instrumentation for measuring neutron fluences and doses at the Lawrence Livermore Laboratory RTNS facility are described, primarily for information to outside users of this facility. The results of an intercomparison of the dosimeters are given, and the accuracy of the fluence determination is discussed.
Date: July 1, 1976
Creator: Barschall, H. H.; Booth, R. & Wong, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Differential integral experiments for testing cross section evaluations for fusion reactors

Description: The conceptual design of fusion reactors and fusion-fission hybrid reactors brings into focus a large number of problems dealing with the interaction of 14-MeV neutrons with materials to be used in the design of the different components of the reactor. These components include the first wall, the blanket, the magnets and the shielding system. The accuracy of the design calculations can be assured, providing the transport codes correctly describe the interaction of 14-MeV neutrons with these mat… more
Date: April 1, 1977
Creator: Hansen, L. F.; Anderson, J. D.; Wong, C. & Komoto, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mica fission detectors

Description: The present development status of the mica fission detectors is summarized. It is concluded that the techniques have been refined and developed to a state such that the mica fission counters are a reliable and reproducible detector for fission events.
Date: June 2, 1977
Creator: Wong, C.; Anderson, J. D.; Hansen, L.; Lehn, A. V. & Williamson, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of the neutron emission spectra from spheres of N, O, W, /sup 235/U, /sup 238/U, and /sup 239/Pu, pulsed by 14-MeV neutrons

Description: Inspired by new detector instrumentation that is insensitive to gamma-ray background and improved deuteron-beam bunching and sweeping of the ICT accelerator, we have measured the high-energy (2 less than E/sub n/ less than 15 MeV) neutron emission spectra from spherical targets of nitrogen, oxygen, tungsten, /sup 235/U, /sup 238/U, and /sup 239/Pu. The targets were pulsed at the center by a nominal 14-MeV neutron source at the LLL time-of-flight facility. The neutron source was obtained from th… more
Date: December 15, 1976
Creator: Webster, W. & Wong, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation doses as a function of the thickness and shielding material surrounding a 14-MeV neutron source

Description: The neutron and gamma does for tissue approximation resulting from a 14-MeV neutron source have been calculated as a function of the shielding material and its thickness surrounding the source. The calculations have been carried out for water, concrete, and iron, for thicknesses varying between one and ten mean free paths (mfp). The calculated neutron and gamma spectra emerging from the spherical shielding materials have been compared with measurements for 1.1 to 2.0 mfp of water, 2.1 and 3.9 m… more
Date: April 1, 1977
Creator: Hansen, L. F.; Komoto, T. & Wong, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determination of 235U/238U Ratio on Urine by ICP-MS

Description: LLNL Internal Dosimetry Program - The new procedure satisfies the requirement to determine {sup 235}U/{sup 238}U ratio in bioassay urine samples. MDA - The L{sub C} and MDA{sub 95} for {sup 235}U are well below the required detection limit of 0.00035 {mu}g/L. Turn around time - Analysis of 10 samples plus 2 QCs can be completed in one work day (8 hours).
Date: October 19, 2011
Creator: Collins, L.; Gobaleza, A.; Langston, R.; Radev, R.; Than, C.; Wong, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neutron scattering on deformed nuclei

Description: Measurements of neutron elastic and inelastic differential cross sections around 14 MeV for /sup 9/Be, C, /sup 181/Ta, /sup 232/Th, /sup 238/U, and /sup 239/Pu have been analyzed using a coupled channel (CC) formalism for deformed nuclei and phenomenological global optical model potentials (OMP). For the actinide targets these results are compared with the predictions of a semi-microscopic calculation using Jeukenne, Lejeune, and Mahaux (JLM) microscopic OMP and a deformed ground state nuclear … more
Date: September 1, 1984
Creator: Hansen, L. F.; Haight, R. C.; Pohl, B. A.; Wong, C. & Lagrange, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Summary of measurements and calculations of neutron and gamma-ray emission spectra from spheres pulsed with 14-MeV neutrons

Description: A tabulation of the spherical assemblies for which the transport of 14-MeV neutrons have been measured using pulsed sphere and time-of-flight techniques is presented. The description of the measurements and their comparison with the predictions of LLNL Monte Carlo calculations using the ENDL and ENDF (III to V versions) libraries can be found in the publications listed in the references.
Date: November 1, 1982
Creator: Hansen, L. F.; Komoto, T. T.; Pohl, B. A. & Wong, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Far Scrape-Off Layer and Near Wall Plasma Studies in DIII-D

Description: Far scrape-off layer (SOL) plasma parameters in DIII-D depend strongly on the discharge density and confinement regime. In L-mode, cross-field transport increases with the average discharge density and elevates the far SOL density, thus increasing plasma-wall contact. Far SOL density near the low field side (LFS) of the main chamber wall also increases with decreasing plasma current and with decreasing outer wall gap. In H-mode, between edge localized modes (ELMs), plasma-wall contact is weaker… more
Date: December 3, 2004
Creator: Rudakov, D.; Boedo, J.; Moyer, R.; Brooks, N.; Doerner, R.; Evans, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Engineering design of ARIES-III

Description: An efficient organic cooled low activation ferritic steel first wall and shield has been designed for the D-{sup 3}He power reactor ARIES-III. The design allows removal of the large surface heat load without exceeding temperature and stress design limits. The structure is expected to last for the whole reactor life. The major concerns regarding using the organic coolant in fusion reactors have been greatly alleviated.
Date: July 1, 1993
Creator: Sze, D. K.; Wong, C. & Cheng, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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