Prism reactor system design and analysis of postulated unscrammed events (open access)

Prism reactor system design and analysis of postulated unscrammed events

Key safety characteristics of the PRISM reactor system include the passive reactor shutdown characteristic and the passive shutdown heat removal system, RVACS. While these characteristics are simple in principle, the physical processes are fairly complex, particularly for the passive reactor shutdown. It has been possible to adapt independent safety analysis codes originally developed for the Clinch River Breeder Reactor review, although some limitations remain. In this paper, the analyses of postulated unscrammed events are discussed, along with limitations in the predictive capabilities and plans to correct the limitations in the near future. 6 refs., 4 figs.
Date: August 1, 1991
Creator: Van Tuyle, G.J. & Slovik, G.C.
System: The UNT Digital Library
Three-dimensional simulation of a hole-coupled FEL oscillator (open access)

Three-dimensional simulation of a hole-coupled FEL oscillator

The performance of a two-mirror resonator with holes for out-coupling has been examined in a previous study in which the FEL gain was neglected, but the geometrical effect of the wiggler aperture was included in the optical calculation. The phenomenon of mode degeneracy was found to occur, that has serious implications for the stability of performance when the FEL gain is included. We have developed a FEL oscillator code based on TDA'', a three-dimensional FEL amplifier code, to study the mode characteristics in the presence of an FEL. We find that the interaction of the radiation and the FEL has an important, and positive, impact on the mode-profile and related cavity performance parameters. In particular, mode degeneracy is not expected to be a serious problem for reasonable FEL oscillator designs. 8 refs., 4 figs., 1 tab.
Date: August 1, 1991
Creator: Krishnagopal, S.; Xie, M.; Kim, K. J. & Sessler, A.
System: The UNT Digital Library
Summary and conclusions (open access)

Summary and conclusions

This report presents a brief summary of the author's impressions from SQUID 91.
Date: August 1, 1991
Creator: Clarke, J.
System: The UNT Digital Library
Discrete cavity model of a standing-wave free-electron laser (open access)

Discrete cavity model of a standing-wave free-electron laser

A standing-wave free-electron laser (SWFEL) has been proposed for use in a two-beam accelerator (TBA). Unlike a conventional microwave free-electron laser, the SWFEL has a wiggler that is divided by irises into a series of standing-wave cavities, and the beam is reaccelerated by induction cells between cavities. We introduce a one-dimensional discrete-cavity model of the SWFEL. In contrast to the continuum model that has been extensively used to study the device, the new model takes into account time-of-flight effects within the cavity and applies the reacceleration field only between cavities, where the pondermotive force is absent. As in previous SWFEL models, only a single frequency is considered. Using this model, effects of finite cavity length are investigated. For moderately long cavities, it is shown that there are no adverse effects on the phase stability of the device. 4 refs., 3 figs., 1 tab.
Date: August 1, 1991
Creator: Rangarajan, G.; Sessler, A. (Lawrence Berkeley Lab., CA (United States)) & Sharp, W.M. (Lawrence Livermore National Lab., CA (United States))
System: The UNT Digital Library
Quantum cosmology on the worldsheet (open access)

Quantum cosmology on the worldsheet

Two-dimensional quantum gravity coupled to conformally invariant matter central c > 25 provides a toy model for quantum gravity in four dimensions. Two-dimensional quantum cosmology can thus be studied in terms of string theory in background fields. The large scale cosmological constant depends on non-linear dynamics in the string theory target space and does not appear to be suppressed by wormhole effects. 13 refs.
Date: August 1, 1991
Creator: Cooper, A.R.; Susskind, L. & Thorlacius, L.
System: The UNT Digital Library
Mild coal gasification: Product separation, pilot-unit support, twin screw heat transfer, and H sub 2 S evolution (open access)

Mild coal gasification: Product separation, pilot-unit support, twin screw heat transfer, and H sub 2 S evolution

Our general objective is to further the development of efficient continuous mild coal gasification processes. Our efforts this year have been in four main areas. A new thrust has been to identify and develop efficient processes to separate the vapor product stream into particulate-free liquid and mist-free gas. We continued work aimed at predicting heat transfer rates (hence throughput) in externally-heated twin-screw pyrolyzers. We sought to provide technical support for the design, installation, startup, and operation of the DOE-sponsored 500 kg/hr twin-screw mild gasification unit at Coal Technology Corporation (CTC). A smaller laboratory effort had the objective of identifying and testing the reaction mechanisms of sulfur species during coal pyrolysis. Detailed subproject objectives are given in their respective sections. 20 refs., 4 figs., 1 tab.
Date: August 9, 1991
Creator: Camp, D. W.; Wallman, P. H. & Coburn, T. T.
System: The UNT Digital Library
Identifying the origin of new gauge bosons at the SSC and LHC (open access)

Identifying the origin of new gauge bosons at the SSC and LHC

The ability of an SCD-like detector to identify the origin of a new neutral gauge boson Z{sub 2}, once it has been discovered at the SSC and/or LHC, is examined. 9 refs., 3 figs.
Date: August 1, 1991
Creator: Hewett, J. L. & Rizzo, T. G.
System: The UNT Digital Library
On reactor type comparisons for the next generation of reactors (open access)

On reactor type comparisons for the next generation of reactors

In this paper, we present a broad comparison of studies for a selected set of parameters for different nuclear reactor types including the next generation. This serves as an overview of key parameters which provide a semi-quantitative decision basis for selecting nuclear strategies. Out of a number of advanced reactor designs of the LWR type, gas cooled type, and FBR type, currently on the drawing board, the Advanced Light Water Reactors (ALWR) seem to have some edge over other types of the next generation of reactors for the near-term application. This is based on a number of attributes related to the benefit of the vast operating experience with LWRs coupled with an estimated low risk profile, economics of scale, degree of utilization of passive systems, simplification in the plant design and layout, modular fabrication and manufacturing. 32 refs., 1 fig., 3 tabs.
Date: August 22, 1991
Creator: Alesso, H.P. & Majumdar, K.C.
System: The UNT Digital Library
FEL gain taking into account diffraction and electron beam emittance; generalized Madey's theorem (open access)

FEL gain taking into account diffraction and electron beam emittance; generalized Madey's theorem

We derive a formula for the free electron laser gain in the small-signal, low-grain regime which resembles closely the 1-D formula but taking into account the effect of wave diffraction and electron beam divergence and betatron motion. The formula is cast in a form which exhibits clearly the role of the transverse phase space distribution of photons and electrons. 8 refs.
Date: August 1, 1991
Creator: Kim, Kwang-Je.
System: The UNT Digital Library
Probing the flavor changing vertex of the top-quark (open access)

Probing the flavor changing vertex of the top-quark

The implications of the flavor changing neutral current vertex, t {yields} cX, where X = {gamma},g, Z, or H is examined in the Standard and two-Higgs-doublet models. 9 refs., 3 figs.
Date: August 1, 1991
Creator: Eilam, G. (Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Physics); Hewett, J.L. (Argonne National Lab., IL (United States). High Energy Physics Div.) & Soni, A. (Brookhaven National Lab., Upton, NY (United States))
System: The UNT Digital Library
MBE-4 experiments with bright Cesium+ beams (open access)

MBE-4 experiments with bright Cesium+ beams

Since 1985 the Heavy Ion Fusion Accelerator Research program at the Lawrence Berkeley Laboratory has been studying current amplification and emittance variations in MBE-4, a four-cesium-beam ion induction linac. This experiment models much of the accelerator physics of the electrostatically focused section of a fusion driver. Four space-charged Cs{sup +} beams, initially about one meter in length at currents of 5--10 mA, are focused by electrostatic quadrupoles and accelerated in parallel from approximately 200 keV up to one MeV by 24 accelerating gaps. Final currents of 20--40 mA per beam are typical. Recent experiments with extremely low emittance beams ({var epsilon}{sub n}=0.03 {pi}mm-mRad) have investigated variations of transverse and longitudinal normalized emittance for drifting and accelerating beams. Experiments show that very cold ({sigma}{sub o}=72{degrees},{sigma}=6{degrees}), off-axis or poorly matched beams increase transverse emittance when drifted or accelerated through these MBE-4 apparatus. Only by carefully centering and matching the beams can acceleration at constant normalized emittance be achieved. Warmer beams with less tune depression exhibit little to no emittance growth and show smaller emittance fluctuations when off axis or mis-matched. 10 refs., 10 figs.
Date: August 1, 1991
Creator: Fessenden, T.J.
System: The UNT Digital Library
Predicted performance of an Induction Linac Driven FEL amplifier designed for radar applications at 94 GHz (open access)

Predicted performance of an Induction Linac Driven FEL amplifier designed for radar applications at 94 GHz

The saturated performance of an Induction Linac Driven FEL operating at 94 GHz with peak microwave powers in excess of 2 GW is evaluated using a self-consistent 3D waveguide mode-particle interaction code. The code includes the effect of AC longitudinal space charge and DC transverse space charge with the resulting prediction that operation is not possible below 2.5 MeV with a 2 kA beam and 10 cm wiggler. A design based around a 4 MeV beam predicts peak power in excess of 2.4 GW over a 10% bandwidth with output phase varying linear with frequency. 2 refs., 5 figs., 1 tab.
Date: August 1, 1991
Creator: Caplan, M.
System: The UNT Digital Library
Technology transfer in the national laboratories (open access)

Technology transfer in the national laboratories

The title of this paper might unfairly provoke readers if it conjures up visions of vast stores of high-tech gadgets in several hundred technology warehouses'' (also known as federal laboratories) around the country, open for browsing by those in search of a bargain. That vision, unfortunately, is a mirage. The term technology transfer'' is not really as accurate as is the term technology team-work,'' a process of sharing ideas and knowledge rather than widgets. In addition, instead of discussing the efforts of more than 700 federal labs in the US, I mean to address only those nine government-owned, contractor-operated multiprogram labs run by the Department of Energy. Nevertheless, the topic of technology team-work opportunities with DOE multiprogram national lab is of significance to those concerned with increasing economic competitiveness and finding technological solutions to a host of national problems. A significant fraction of US R D capabilities rests in the nine DOE multiprogram national laboratories -- and these labs have only just begun to join the other federal laboratories in these efforts due to the passage and recent implementation of the National Competitiveness Technology Transfer Act of 1989.
Date: August 1, 1991
Creator: Yonas, G.
System: The UNT Digital Library
Radiation-driven evolution of low-mass x-ray binaries and the formation of millisecond pulsars (open access)

Radiation-driven evolution of low-mass x-ray binaries and the formation of millisecond pulsars

Recent data on low-mass X-ray binaries (LMXBs) and millisecond pulsars (MSPs) pose a challenge to evolutionary theories which neglect the effects of disk and comparison irradiation. Here we discuss the main features of a radiation-driven (RD) evolutionary model that may be applicable to several LMXBs. According to this model, radiation from the accreting compact star in LMXBs vaporizes'' the accretion disk and the companion star by driving a self-sustained mass loss until a sudden accretion-turn off occurs. The main characteristics of the RD-evolution are: (1) lifetime of RD-LMXB's is of order 10{sup 7} years or less; (2) both the orbital period gap and the X-ray luminosity may be consequences of RD-evolution of LMXB's containing lower main sequence and degeneration companion stars; (3) the companion star may transfer mass to the primary even if it underfills its Roche lobe; (4) a class of recycled MSPs can continue to vaporize the low-mass companions by a strong pulsar wind even after the accretion turn-off; (5) the RD-evolutionary model resolves the apparent statistical descrepancy between the number of MSPs and their LMXB progenitors in the Galaxy. We discuss the implications of the discovery of single MSPs in low-density globular clusters and the recent measurements …
Date: August 8, 1991
Creator: Tavani, M. (Lawrence Livermore National Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Astronomy)
System: The UNT Digital Library
The application of the ADSP-21020 40-bit floating point DSP microprocessor in a digital Doppler radar (open access)

The application of the ADSP-21020 40-bit floating point DSP microprocessor in a digital Doppler radar

A continuous wave doppler radar system has been designed which is portable, easily deployable and can be remotely controlled. The system is immune to ground clutter and is used for wind speed detection and direction determination. Nearly real time digital signal processing is performed by an Analog Devices ADSP-21020, a 40-bit floating point Digital Signal Processing (DSP) microprocessor. This paper provides an overview of the design of the system including the radio frequency (RF) to digital interface. The various DSP detection algorithms are discussed and compared to system performance and sensitivity. Finally, DSP performance is compared to the performance of an earlier system using Analog Device's ADSP-2100. 6 refs.
Date: August 26, 1991
Creator: Robinson, S. H. & Morrison, R. E.
System: The UNT Digital Library
Environmental issues in planning building energy technologies R D in the United States (open access)

Environmental issues in planning building energy technologies R D in the United States

The US Department of Energy's Office of Building Technologies (OBT) has begun studies on the relationship and impact of buildings energy use on the environment, particularly with respect to global climate change, acid rain, stratospheric ozone depletion, and indoor air quality. The paper presents an overview of international and US federal activity in global change to set OBT's activities in context. The paper then reviews briefly the contribution of buildings to atmospheric problems through building energy use. OBT's program primarily supports projects with indirect environmental impacts through energy efficiency (e.g., thermally activated heat pumps use natural gas instead of electricity) and the use of renewables in buildings. The paper briefly describes the OBT program and covers an inventory of projects that OBT has funded on environmental/building problems. Analyses have included three kinds of topics: (1) CFC substitutes for refrigeration equipment, (2) incorporating the cost of externalities into utility electricity generation, and (3) indoor air quality. The paper shows how environmental issues are being taken into account in planning the US R D program in building energy technologies. 27 refs.
Date: August 1, 1991
Creator: Farhar, B.C. (Solar Energy Research Inst., Golden, CO (United States)); Abel, F.H. (USDOE, Washington, DC (United States)); Nicholls, A.K. (Pacific Northwest Lab., Richland, WA (United States)) & Millhone, J.P. (USDOE Assistant Secretary for Conservation and Renewable Energy, Washington, DC (United States). Office of the Deputy Assistant Secretary for Building Technologies)
System: The UNT Digital Library
Underground muons observed in the Soudan 2 detector from the directions of x-ray sources (open access)

Underground muons observed in the Soudan 2 detector from the directions of x-ray sources

We report on observations of underground muons made with the Soudan 2 proton decay detector at a depth of 2090 mwe from the directions of the binaries Hercules X-1 and 1E2259+586 and the Crab pulsar.
Date: August 1, 1991
Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Giles, R. H.; Perkins, D. H. et al.
System: The UNT Digital Library
The complexation behavior of neptunium and plutonium with nitrilotriacetic acid (open access)

The complexation behavior of neptunium and plutonium with nitrilotriacetic acid

The first stability constant of NpO{sub 2}{sup +} with nitrilotriacetic acid (NTA) was determined at four ionic strengths (0.5, 1.0, 2.0, 3.0 M) using spectrophotometry. Nonlinear least-squares data fitting identified the complex as NpO{sub 2}NTA{sup 2-}. The Specific Ion Interaction Theory (S.I.T) approximation method was used to determine the stability constants at infinite dilution. First results on Pu{sup 4+} and PuO{sub 2}{sup 2+} complexation with NTA are reported. The stability constant for the Pu(NTA){sup +} complex at I = 0.1 M strength is given. From results for PuO{sub 2}{sup 2+} complexation with NTA (I = 1 M) at pH < 3, the stability constant was derived for PuO{sub 2} NTA{sup {minus}}. At pH > 3, NTA partially reduced PuO{sub 2}{sup 2+} to PuO{sub 2}{sup +}. 3 refs., 5 figs., 4 tabs.
Date: August 1, 1990
Creator: Nitsche, H. & Becraft, K.
System: The UNT Digital Library
Profiling and Mapping of Advanced Materials Using Spatially Resolved Raman Spectroscopy (open access)

Profiling and Mapping of Advanced Materials Using Spatially Resolved Raman Spectroscopy

We have developed a technique to profile important physical and chemical properties of materials based upon simultaneous acquisition of Raman spectra along a laser illumination line, coupled with extensive and rapid spectral analysis to extract the desired information. The technique uses a two-dimensional spectroscopic detector and, in contrast to Hadamard techniques, sample movement in one dimension that allows all collected light to be detected. Property maps comprised of the analysis results of more than 10,000 Raman spectra can be built up from successive profiles in a few hours. In order to increase efficiency, the data for one profile are analyzed while the data for the next profile are collected. Two recent applications are discussed: measuring spatial variations in crystalline quality in CVD-grown diamond thin films and mapping transformed zones produced by compressive stress in a bulk sample of phase-stabilized zirconia (PSZ).
Date: August 1, 1991
Creator: Ager, Joel; Veirs, D. K.; Lee, H. Q. & Rosenblatt, G. M.
System: The UNT Digital Library
Simultaneous observations of extensive air showers and underground muons at Soudan 2 (open access)

Simultaneous observations of extensive air showers and underground muons at Soudan 2

We have built a small proportional tube air shower array on the surface above the Soudan 2 proton decay detector in Soudan, Minnesota, USA. This array, in coincidence with the underground detector, allows simultaneous surface and underground observations of high energy cosmic ray showers. These observations, still in their initial stages, may eventually be able to provide information about the composition of cosmic ray primaries in the knee'' region of the energy spectrum. 4 refs.
Date: August 1, 1991
Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Giles, R. H.; Perkins, D. H. et al.
System: The UNT Digital Library
Comparison of measurements of aerosol elemental carbon at Wrangel Island, USSR, and Barrow, Alaska (open access)

Comparison of measurements of aerosol elemental carbon at Wrangel Island, USSR, and Barrow, Alaska

During the winter and spring seasons of 1989 and 1990, we collected samples of the background aerosol at Wrangel Island in the eastern Soviet Arctic. The samples were analyzed by optical transmission to determine the concentration of aerosol black'' carbon (BC), with results ranging from 5 to 167 nanograms per standard cubic meter. These results are compared with the continuous measurements at the NOAA/CMDL monitoring station at Barrow, Alaska for cases when meteorological trajectories connected the two locations with transit times of from one to two days. The preliminary results suggest that concentrations of aerosol BC are reduced at Wrangel relative to Barrow.
Date: August 1, 1991
Creator: Polissar, A. V.; Kapustin, V. N. & Hansen, A. D. A.
System: The UNT Digital Library
B-Factories (open access)

B-Factories

The evolution of B-Factories is discussed, and comments are made about the common features of present-day asymmetric storage ring collider designs. 11 refs., 1 tab.
Date: August 1, 1991
Creator: Siemann, R.
System: The UNT Digital Library
Results from p p colliders (open access)

Results from p p colliders

Recent results {bar p}p colliders are presented. From elastic scattering experiments at the Tevatron, an average value of {sigma}{sub tot} = 72.1{plus minus}2 mb is reported, along with a new measurement of {rho} = 0.13 {plus minus} 0.7. New measurements of jet direct photon and high p{sub t} W and Z production are compared to more precise, higher order predictions from perturbative QCD. Recently available data on the W mass and width give combined values for M{sub W} = 80.14{plus minus}0.27 GeV/c{sup 2}, and {Gamma}(W) =2. 14 {plus minus} 0.08 GeV. From electroweak radiative corrections and M{sub W}, one finds M{sub top} = 130{plus minus}40 GeV/c{sup 2}, with a 95% C.L. upper limit at 210 GeV/c{sup 2}. Current limits on M{sub top} are presented, along with a review of the prospects for top discovery. From jet data there is no evidence of quark substructure down to the distance scale of 1.4 {times} 10{sup {minus}17} cm, nor is there evidence for supersymmetry or heavy gauge bosons at {bar p}p colliders, allowing lower limits on M{sub W}, > 520 GeV/c{sup 2} and M{sub Z} 412 GeV/c{sup 2}. 66 refs., 26 figs.
Date: August 1, 1991
Creator: Huth, J.
System: The UNT Digital Library
Compatibility of Halthane 88-3 urethane adhesive with the replacement cleaning solvent D-Limonene (open access)

Compatibility of Halthane 88-3 urethane adhesive with the replacement cleaning solvent D-Limonene

D-Limonene, (R)1-methyl-4-isopropenyl-1-cyclohexene, has been identified as a leading replacement for chlorinated solvents traditionally used to clean electrical assemblies and critical components in some phases of weapons production. Unfortunately, d-limonene has a much lower vapor pressure than the chlorinated solvents if replaces (<2 torr at ambient). This makes its complete elimination from cleaned subassemblies potentially difficult, and gives rise to concerns about the compatibility of d-limonene with materials in the warhead. During the past year many WR polymers and adhesives have been surveyed for their compatibility with d-limonene. Preliminary test results obtained at Sandia (Albuquerque) and Allied-Signal (KCD) showed that Aluminum/Halthane 88-3/Aluminum joints were destroyed during exposure to saturated d-limonene vapor. The cause of bond failure appeared to be d-limonene induced swelling of the Halthane polymer. This report describes recent work performed at LLNL to study the swelling behavior and bond strength degradation of Halthane 88-3 resulting from exposure to d-limonene vapor.
Date: August 1, 1991
Creator: LeMay, J.D. & Mendoza, B.
System: The UNT Digital Library