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Stark broadening of isolated lines from high-Z emitters in dense plasmas

Description: The joint distribution of the electric microfield and its longitudinal derivative is required for the calculation of line profiles for the He-like ions in very dense plasmas. We used a molecular dynamics code to compute exact distributions in single- and multi-component plasmas, and then we investigated various analytical approximations to these results. We found that a simplified, two-nearest-neighbor scheme leads to surprisingly accurate distribution functions. Our results are illustrated by … more
Date: September 1, 1980
Creator: Weisheit, J.C. & Pollock, E.L.
Partner: UNT Libraries Government Documents Department
open access

Automatic program timing profiles with FTN4

Description: Design of a scheme for producing execution timing profiles of FORTRAN programs automatically is proposed with a recommendation to implement it as an option to the compiler. An experimental implementation on the LBL 7600 is also described. 1 figure.
Date: September 1, 1980
Creator: Friedman, R.
Partner: UNT Libraries Government Documents Department
open access

High beta studies on ISX-B with neutral beam injection

Description: Injection of H/sup 0/ into D/sup +/ plasmas with beam power P/sub b/ of up to 1.7 MW has produced rms betas of approx. 4%, volume-averaged betas of approx. 3%, and central betas of approx. 10% in the ISX-B tokamak. Although theoretical calculations indicate that the observed equilibria may be unstable to ballooning modes, no catastrophic loss of confinement has been observed, and beta continues to increase with injection power. In these beam-dominated high-beta discharges the electron and ion e… more
Date: September 1980
Creator: Sheffield, J.; Bates, S.C. & Bush, C.E.
Partner: UNT Libraries Government Documents Department
open access

Technology for large tandem mirror experiments

Description: Construction of a large tandem mirror (MFTF-B) will soon begin at Lawrence Livermore National Laboratory (LLNL). Designed to reach break-even plasma conditions, the facility will significantly advance the physics and technology of magnetic-mirror-based fusion reactors. This paper describes the objectives and the design of the facility.
Date: September 4, 1980
Creator: Thomassen, K.I.
Partner: UNT Libraries Government Documents Department
open access

Performance and development of dE/dx counters

Description: The performance of existing or nearly completed detectors for particle identification by using the relativistic rise of energy loss will be discussed. Detailed analysis of systematic errors leads finally to large detector systems approaching the ultimate resolution as measured in small test devices. New methods for extracting the information from the counter with the potential of better particles separation than standard dE/dx will be presented. It includes very fine sampling, delta-ray clippin… more
Date: September 1, 1980
Creator: Walenta, A. H.
Partner: UNT Libraries Government Documents Department
open access

Shiva automatic pinhole alignment

Description: This paper describes a computer controlled closed loop alignment subsystem for Shiva, which represents the first use of video sensors for large laser alignment at LLNL. The techniques used on this now operational subsystem are serving as the basis for all closed loop alignment on Nova, the 200 terawatt successor to Shiva.
Date: September 5, 1980
Creator: Suski, G.J.
Partner: UNT Libraries Government Documents Department
open access

RODCON: a finite difference heat conduction computer code in cylindrical coordinates

Description: RODCON, a finite difference computer code, was developed to calculate the internal temperature distribution of the fuel rod simulator (FRS) for the Core Flow Test Loop (CFTL). RODCON solves the implicit, time-dependent forward-differencing heat transfer equation in 2-dimensional (Rtheta) cylindrical coordinates at an axial plane with user specified radial material zones and surface conditions at the FRS periphery. Symmetry of the boundary conditions of coolant bulk temperatures and film coeffic… more
Date: September 16, 1980
Creator: Conklin, J. C.
Partner: UNT Libraries Government Documents Department
open access

Hybrid reactors. [Fuel cycle]

Description: The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain… more
Date: September 9, 1980
Creator: Moir, Ralph W.
Partner: UNT Libraries Government Documents Department
open access

Physical protection solutions for security problems at nuclear power plants. [PWR; BWR]

Description: Under Department of Energy sponsorship, Sandia National Laboratories has developed a broad technological base of components and integrated systems to address security concerns at facilities of importance, including nuclear reactors. The primary security concern at a light water reactor is radiological sabotage, a deliberate set of actions at a plant which could expose the public to a significant amount of radiation (on the order of 10 CFR 100 limits). (Also of importance to plant operators are … more
Date: September 1, 1980
Creator: Darby, J.L. & Jacobs, J.
Partner: UNT Libraries Government Documents Department
open access

Background field coils for the High Field Test Facility

Description: The High Field Test Facility (HFTF), presently under construction at LLNL, is a set of superconducting coils that will be used to test 1-m-o.d. coils of prototype conductors for fusion magnets in fields up to 12 T. The facility consists of two concentric sets of coils; the outer set is a stack of Nb-Ti solenoids, and the inner set is a pair of solenoids made of cryogenically-stabilized, multifilamentary Nb/sub 3/Sn superconductor, developed for use in mirror-fusion magnets. The HFTF system is d… more
Date: September 22, 1980
Creator: Zbasnik, J. P.; Cornish, D. N.; Scanlan, R. M.; Jewell, A. M.; Leber, R. L.; Rosdahl, A. R. et al.
Partner: UNT Libraries Government Documents Department
open access

Open and hidden charm muoproduction. [209 GeV]

Description: New results are presented on open and hidden charm and bottom production by 209-GeV muons interacting in a magnetized steel calorimeter. The upper limit on the production of T states by muons is sigma(..mu..N ..-->.. ..mu..UPSILONX)B(UPSILON ..-->.. ..mu mu..) < 22 x 10/sup -39/ cm/sup 2/ (90% confidence level). The distributions of elastically produced psi's are consistent with s-channel helicity conservation (SCHC) and disagree with psi dominance. From analysis of dimuon final states the cros… more
Date: September 1, 1980
Creator: Clark, A.R.; Johnson, K.J. & Kerth, L.T.
Partner: UNT Libraries Government Documents Department
open access

Positron computed tomography: current state, clinical results and future trends

Description: An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)
Date: September 1, 1980
Creator: Schelbert, H. R.; Phelps, M. E. & Kuhl, D. E.
Partner: UNT Libraries Government Documents Department
open access

Normalizing the renormalization group in deep inelastic leptoproduction. CTP No. 878

Description: The quark-bag model is used to calculate the nucleon matrix elements of local twist-two operators. Bag matrix elements applicable to low Q/sup 2/ are evolved by use of QCD perturbation theory to a value of Q/sup 2/ large enough that the data can be expected to be dominated by twist-two. Nonsinglet moments of F/sub 3/ are plotted. Although only twist-two was studied, the work has implications for higher twist. It is concluded that either the twist-two operator matrix element is Q/sup 2/ dependen… more
Date: September 1, 1980
Creator: Jaffe, R.L.
Partner: UNT Libraries Government Documents Department
open access

Analysis of the new GCFR upper and lower plenum flow-through shields

Description: Analysis of the proposed GCFR upper and lower plenum flow-through shields has been performed using both discrete ordinate (DOT) and Monte Carlo (MORSE) methods. Several shields having one change of direction in the coolant path (chevron) and two changes of direction (herringbone) were investigated. The shields were modeled as unit cells with periodic boundary conditions. From plenum fluence calculations and design constraints at the reactor vessel liner, it was determined that all the shield co… more
Date: September 14, 1980
Creator: Cramer, S.N. (Oak Ridge National Lab., TN); Reed, D.A.; Emmett, M.B. & Rouse, C.A.
Partner: UNT Libraries Government Documents Department
open access

Low energy weak interactions and decays. [Partial summary of presentations at XXth International Conf. on High Energy Physics, Madison, Wisc. , July 17-23, 1980]

Description: Results presented during sessions B5 to 7 at the XXth International Conference on High Energy Physics (University of Wisconsin, Madison, July 17 to 23, 1980) are discussed. Essentially all the material presented is summarized. The sessions covered various aspects of low-energy weak interactions. The following topics are addressed: CP-invariance violation, high-statistics study of ..lambda.. beta decay, parity violation in proton-nucleus scattering at 6 GeV/c, new results on the tau, charm parti… more
Date: September 1, 1980
Creator: Trilling, G.H.
Partner: UNT Libraries Government Documents Department
open access

Proceedings of the heavy ion fusion workshop

Description: Separate abstracts were prepared for 35 of the included papers. Abstracts for 9 of the remaining papers appeared earlier in ERA. Two of the included papers were title listed only. (MOW)
Date: September 1, 1980
Creator: Herrmannsfeldt, W.B. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Two-photon results from SPEAR

Description: Results obtained by two experiments at SPEAR on the two-photon production of lepton pairs and resonances are reported. Both experiments find agreement of lepton production with QED expectations, and observe an enhancement of the ..pi pi.. mass spectrum in the 1250 MeV/c/sup 2/ region. The Mark II finds this enhancement not consistent with the decay of the f(1270 MeV/c/sup 2/) alone. The ..gamma gamma.. partial width of the eta' has also been measured by the Mark II.
Date: September 1, 1980
Creator: Roussarie, A.
Partner: UNT Libraries Government Documents Department
open access

Test results from the 500 kW direct contact pilot plant at East Mesa

Description: A 500 kW power plant utilizing direct contact heat exchange (DCHX) between the geothermal brine and the isobutane (IC/sub 4/) working fluid is being operated at the East Mesa test facility. The power plant incorporates a 40-inch-diameter direct-contactor approximately 35 feet tall. The purpose of the pilot plant is to determine the feasibility of large-scale direct-contact heat exchange and power plant operation with the DCHX. The binary cycle offers higher conversion factors (heat energy trans… more
Date: September 1, 1980
Creator: Nichols, K.E.; Olander, R.G. & Lobach, J.L.
Partner: UNT Libraries Government Documents Department
open access

Progress in direct heat applications projects

Description: The development of hydrothermal energy for direct heat applications is being aided by twenty-two demonstration projects that are funded on a cost-sharing basis by the US Department of Energy, Division of Geothermal Energy. These projects are designed to demonstrate the technical and economic feasibility of the direct use of geothermal heat in the United States. Twelve of these projects are administered by the DOE-Idaho Operations Office with technical support from EG and G Idaho, Inc. Engineeri… more
Date: September 9, 1980
Creator: Childs, F. W.; Jones, K. W.; Nelson, L. B.; Strawn, J. A. & Tucker, M. K.
Partner: UNT Libraries Government Documents Department
open access

Potential for meeting IAEA safeguards goals for reprocessing

Description: The author concludes that: Safeguards which allow the meeting of IAEA uranium and plutonium diversion detection goals for large-scale reprocessing plants are achievable. Concepts exists for ways in which IAEA inspectors could verify data received from operations of such facilities. Additional work is needed, particularly in the futher development of on-line instruments. Computerized near real-time accounting systems may provide significant operational benefits in addition to being required for … more
Date: September 1, 1980
Creator: Bambas, K.J.
Partner: UNT Libraries Government Documents Department
open access

Relationship between the DOE loan guaranty and California Environmental Quality Act environmental review processes

Description: The US Department of Energy (DOE) is involved in numerous geothermal research, development, demonstration, and loan guaranty projects in the State of California. These projects often require the preparation of both an Environmental Impact Report (EIR), as required by California Environmental Quality Act (CEQA), and an Environmental Assessment (EA) or Impact Statement (EIS) as required under NEPA. DOE adoption or utilization of information contained in EIR's to meet that agency's NEPA requiremen… more
Date: September 9, 1980
Creator: Mezga, L. J. & Brechbill, R. A.
Partner: UNT Libraries Government Documents Department
open access

Exclusive processes and hadron dynamics at short distances

Description: The predictions of perturbative QCD for a number of areas of hadron dynamics are discussed, including exclusive processes at large momentum transfer, the endpoint behavior of hadronic structure functions, and the Fock state structure of hadron wave functions, especially their behavior at short distances. New results for exclusive two-photon processes, the normalization of high-twist contributions to the meson structure function, and the calculation of the valence Fock state probability of the p… more
Date: September 1, 1980
Creator: Brodsky, S.J. & Lepage, G.P.
Partner: UNT Libraries Government Documents Department
open access

Microchannel plate as a detector of minimum ionizing particle

Description: Micro-channel plate multipliers have been used to detect the passage of relativistic charged particles. Measurements of the detection efficiency and pulse height response versus micro-channel plate gain are presented for one, two and three micro-channel plate arrays. The probability of detecting an avalanche on the detector anode per one channel of MCP crossed by the relativistic particle was calculated. Temporal response and time jitter were measured and are reported. The track images of beam … more
Date: September 3, 1980
Creator: Oba, K; Rehak, P & Smith, S D
Partner: UNT Libraries Government Documents Department
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