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Heat transfer in inertial confinement fusion reactor systems

Description: The short time and deposition distance for the energy from inertial fusion products results in local peak power densities on the order of 10/sup 18/ watts/m/sup 3/. This paper presents an overview of the various inertial fusion reactor designs which attempt to reduce these peak power intensities and describes the heat transfer considerations for each design.
Date: April 23, 1980
Creator: Hovingh, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Heavy-Ion Elastic Scattering

Description: The elastic scattering of C/sup 12/ ions from Ar, Fe, Ni, Ag/sup 107/ In, and Ta was measured as a function of angle, at a laboratory-system energy of 124.5 Mev with the Berkeley heavy-ion linear accelerator. The experimental equipment and techniques are discussed. The angular distributions show the same general behavior as previous heavy-ion elastic scattering experiments. The experimental data were analyzed with the semiclassical Blair model as modified by McIntyre. Very good agreement with e… more
Date: April 17, 1961
Creator: Alster, Jonas
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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HOTSPUR progress report: neutron source spectrum characterization, and /sup 6/Li(n,x. cap alpha. ) and /sup 7/Li(n,x. cap alpha. ) cross section determination

Description: As a prerequisite to high accuracy measurements involving the bulk configuration of /sup 6/LiD we must have a good grasp of the details of the RTNS-I neutron source energy spectrum. Experiments to this end involving neutron yield vs deuteron energy, ratios of foil activation of selected elements, and pulse height distributions of a Si surface barrier detector are described. With this knowledge, the /sup 4/He-production cross sections for /sup 6/Li and /sup 7/Li are found experimentally to be 0.… more
Date: April 2, 1984
Creator: Goldberg, E. & Haight, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Collisional and chaotic transport of energetic particles in toroidal plasma

Description: We have made progress in three general areas of confinement plasma physics is proposed. We developed an accurate theory for the trapping/detrapping process in tokamaks with ripple and stellarators. We determined the alpha particle distribution in the situation where both collisions and collisionless chaotic (ripple) transport are present.
Date: April 1992
Creator: Cary, J.R. & Shasharina, S.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transfer and breakup reactions at intermediate energies

Description: The origin of the quasi-elastic peak in peripheral heavy-ion reactions is discussed in terms of inelastic scattering and transfer reactions to unbound states of the primary projectile-like fragment. The situation is analogous to the use of reverse kinematics in fusion reactions, a technique in which the object of study is moving with nearly the beam velocity. It appears that several important features of the quasi-elastic peak may be explained by this approach. Projectile-breakup reactions have… more
Date: April 1, 1986
Creator: Stokstad, R.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Overview of Modeling and Simulations of Plutonium Aging

Description: Computer-aided materials research is now an integral part of science and technology. It becomes particularly valuable when comprehensive experimental investigations and materials testing are too costly, hazardous, or of excessive duration; then, theoretical and computational studies can supplement and enhance the information gained from limited experimental data. Such is the case for improving our fundamental understanding of the properties of aging plutonium in the nuclear weapons stockpile. T… more
Date: April 24, 2007
Creator: Schwartz, A J & Wolfer, W G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The New Element Berkelium (Atomic Number 97)

Description: An isotope of the element with atomic number 97 has been discovered as a product of the helium-ion bombardment of americium. This isotope decays with the emission of alpha-particles of maximum energy 6.72 Mev (30 percent) and it emits lower energy alpha-particles of energies 6.55 Mev (53 percent) and 6.20 Mev (17 percent). The half-life of this isotope is 4.6 hours and it decays primarily by electron capture with about 0.1 percent branching decay by alpha-particle emission. The mass number is p… more
Date: April 26, 1950
Creator: Thompson, S. G.; Ghiorso, A. & Seaborg, G. T.
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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The application of thick hydrogenated amorphous silicon layers to charged particle and x-ray detection

Description: We outline the characteristics of thick hydrogenated amorphous silicon layers which are optimized for the detection of charged particles, x-rays and ..gamma..-rays. Signal amplitude as a function of the linear energy transfer of various particles are given. Noise sources generated by the detector material and by the thin film electronics - a-Si:H or polysilicon proposed for pixel position sensitive detectors readout are described, and their relative amplitudes are calculated. Temperature and ne… more
Date: April 1989
Creator: Perez-Mendez, V.; Cho, G.; Fujieda, I.; Kaplan, S. N.; Qureshi, S. & Street, R. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Narrow H-alpha emission profiles in tokamaks: molecular origin and observational effects

Description: The narrow hydrogen Balmer alpha profiles observed in tokamaks are explained in terms of the slow (approx. 0.3 eV) and fast (2 to 6 eV) excited atoms formed by dissociation of molecular hydrogen at the plasma edge. Extra widening of the spectrum in the wings can be explaind by Zeeman split H-alpha that is reflected from the vacuum vessel. This interpretation is consistent with available high-resolution data. The use of H-alpha as a diagnostic is discussed briefly.
Date: April 1, 1981
Creator: McNeill, D.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Achieving high fusion reactivity in high poloidal beta discharges in TFTR

Description: High poloidal beta discharges have been produced in TFTR that achieved high fusion reactivities at low plasma currents. By rapidly decreasing the plasma current just prior to high-power neutral beam injection, relatively peaked current profiles were created having high l[sub i] > 2, high Troyon-normalized beta, [beta]N > 3, and high poloidal beta. [beta][sub p] [ge] 0.7 R/a. The global energy confinement time after the current ramp was comparable to supershots, and the combination of improved M… more
Date: April 1, 1993
Creator: Manuel, M. E.; Navratil, G. A.; Sabbagh, S. A. (Columbia Univ., New York, NY (United States). Dept. of Applied Physics); Batha, S.; Bell, M. G.; Bell, R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Relative Yields of Nitrogen-17 Produced by 190-Mev Deuteron Bombardment

Description: "Yields of N¹⁷ relative to that produced in LiF have been measured in the 190-Mev deflected deuteron and the 380-Mev alpha beams of the 184-inch synchrocyclotron. The measurements have been performed in all the light elements from 0 through V, with the exception of Sc and the noble gases. In addition, yields were measured in the separated isotopes of Mg...Comparisons are made with other types of yield studies performed with neutrons and protons, and the areas of agreement are noted."
Date: April 13, 1955
Creator: Chupp, Warren William
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Evolution of the alpha particle driven toroidicity induced Alfven mode

Description: The interaction of alpha particles with a toroidicity induced Alfven eigenmode is investigated self-consistently by using a kinetic dispersion relation. All important poloidal harmonics and their radial mode profiles are included. A Hamiltonian guiding center code is used to simulate the alpha particle motion. The simulations include particle orbit width, nonlinear particle dynamics and the effects of the modes on the particles. Modification of the particle distribution leading to mode saturati… more
Date: April 1, 1994
Creator: Wu, Y.; White, R. B. & Cheng, C. Z.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ICRF-induced fusion product loss in TFTR

Description: When ICRF power is applied to plasmas in which there is no externally-supplied minority species, an enhanced loss of DD fusion products results. The characteristics of the loss are consistent with particles at or near the birth energy having their perpendicular velocity increased by the ICRF such that those near the passing/trapped boundary are carried into the first orbit loss cone. A rudimentary model of this process predicts losses of a magnitude similar to those seen. Predictions based upon… more
Date: April 1, 1994
Creator: Darrow, D. S.; Chang, C. S. & Zweben, S. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Achieving high fusion reactivity in high poloidal beta discharges in TFTR

Description: High poloidal beta discharges have been produced in TFTR that achieved high fusion reactivities at low plasma currents. By rapidly decreasing the plasma current just prior to high-power neutral beam injection, relatively peaked current profiles were created having high l{sub i} > 2, high Troyon-normalized beta, {beta}N > 3, and high poloidal beta. {beta}{sub p} {ge} 0.7 R/a. The global energy confinement time after the current ramp was comparable to supershots, and the combination of improved M… more
Date: April 1, 1993
Creator: Manuel, M. E.; Navratil, G. A.; Sabbagh, S. A.; Batha, S.; Bell, M. G.; Bell, R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Pacific Northwest Laboratory annual report for 1992 to the DOE Office of Energy Research. Part 4, Physical sciences

Description: This report is divided into the following sections, with technical sections in parentheses: dosimetry research (Chernobyl database, radon alpha irradiation of mammalian cells, cell growth rates in individual colonies), measurement science (ultrahigh resolution studies of molecular structure and dynamics, circular dichroism in hyperfine state resolved photoelectron angular distributions, Sr isotope shifts, capillary electrophoresis-mass spectrometry for DNA adduct research, rapid DNA sequencing … more
Date: April 1, 1993
Creator: Toburen, L. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pacific Northwest Laboratory annual report for 1989 to the DOE (Department of Energy) Office of Energy Research - Part 4: Physical Sciences

Description: This 1989 Annual Report from Pacific Northwest Laboratory (PNL) to the US Department of Energy (DOE) describes research in environment, safety, and health conducted during fiscal year 1989. The report again consists of five parts, each in a separate volume. This volume contains 20 papers. Part 4 of the Pacific Northwest Laboratory Annual Report of 1989 to the DOE Office of Energy Research includes those programs funded under the title Physical and Technological Research.'' The Field T… more
Date: April 1, 1990
Creator: Toburen, L. H.; Stults, B. R. & Mahaffey, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gas release from irradiated solids

Description: Experimental and theoretical aspects of inert gas diffusion and release from solids were discussed. An overview of previous gas release studies was given. Particular emphasis was placed on work done by Elleman, Kelly and Matze. Theoretical approaches to the diffusion and gas release problem were examined. In particular, gas release from single region and composite solids was studied with and without trapping. Results obtained with a computer code developed for a composite solid with reversible … more
Date: April 1, 1976
Creator: Olsen, L. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Plasma Simulation Using Gyrokinetic-Gyrofluid Hybrid Models

Description: We are developing kinetic ion models for the simulation of extended MHD phenomena. The model they have developed uses full Lorentz force ions, and either drift-kinetic or gyro-kinetic electrons. Quasi-neutrality is assumed and the displacement current is neglected. They are also studying alpha particle driven Toroidal Alfven Eigenmodes (TAE) in the GEM gyrokinetic code [Chen 07]. The basic kinetic ion MHD model was recently reported in an invited talk given by Dan Barnes at the 2007 American Ph… more
Date: April 9, 2009
Creator: Parker, Scott
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nanodosimetry and nanodosimetric-based models of radiation action for radon alpha particles. Progress report, July 1, 1991--June 30, 1992

Description: The objective of our research work is to provide -- with the aid of biophysical models of radiation action -- information on human risks following exposure to radon alpha particles. The approach proposed consists of (1) developing appropriate models (parametric and non-parametric) for alpha radiation induction of relevant end points (survival, cellular transformation), (2) providing an accurate physical characterization of the particle tracks in terms of nanodosimetric distributions, (3) suppor… more
Date: April 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Self-consistent study of the alpha particle driven TAE mode

Description: The interaction of high energy particles with an Alfven eigenmode is investigated self-consistently by using a realistic kinetic dispersion relation. All important poloidal mode numbers and their radial mode profiles as calculated with the NOVA-K code are included. A Hamiltonian guiding center code is used to simulate the alpha particle motion. The numerical simulations include particle orbit width, nonlinear particle dynamics and the effects of the modes on the particles. Modification of the p… more
Date: April 1, 1994
Creator: Wu, Y. & White, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Collisional and chaotic transport of energetic particles in toroidal plasma. Progress report

Description: We have made progress in three general areas of confinement plasma physics is proposed. We developed an accurate theory for the trapping/detrapping process in tokamaks with ripple and stellarators. We determined the alpha particle distribution in the situation where both collisions and collisionless chaotic (ripple) transport are present.
Date: April 1992
Creator: Cary, J. R. & Shasharina, S. 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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