Blanket Optimization Studies for Cascade (open access)

Blanket Optimization Studies for Cascade

A nonlinear, multivariable, blanket optimization technique is applied to the Cascade inertial confinement fusion reactor concept. The thickness of a two-zone blanket, which consists of a BeO multiplier region followed by a LiAlO/sub 2/ breeding region, is minimized subject to constraints on the tritium breeding ratio, neutron leakage, and heat generation rate in Al/SiC tendons that support the chamber wall.
Date: February 28, 1985
Creator: Meier, W. R. & Morse, E. C.
Object Type: Article
System: The UNT Digital Library
ICF reactor economics: identifying the high leverage design features (open access)

ICF reactor economics: identifying the high leverage design features

Parametric studies were carried out for a heavy ion beam (HIB) fusion electric power plant to investigate the effects on the cost of electricity (COE) of variations in several design parameters. In particular, we examined the effects of maximum achievable chamber pulse rate, driver cost, target gain, electric conversion efficiency, and net electric power. We find that with a combination of improvements over our base case, HIB fusion can be economically competitive with other future power sources.
Date: February 28, 1985
Creator: Meier, W. R. & Hogan, W. J.
Object Type: Article
System: The UNT Digital Library
ICF tritium production reactor (open access)

ICF tritium production reactor

The conceptual design of an ICF tritium production reactor is described. The chamber design uses a beryllium multiplier and a liquid lithium breeder to achieve a tritium breeding ratio of 2.08. The annual net tritium production of this 532 MW/sub t/ plant is 16.9 kg, and the estimated cost of tritium is $8100/g.
Date: February 28, 1985
Creator: Meier, W. R.; McCarville, T. J.; Berwald, D. H.; Gordon, J. D. & Steele, W. G.
Object Type: Article
System: The UNT Digital Library
AGS broad band neutrino beam (open access)

AGS broad band neutrino beam

We describe the broad band neutrino beam in the north area of the AGS and discuss the calculation of the neutrino flux. The horns were initially designed by Robert Palmer and this beam has been used for almost all neutrino running at the AGS. All of the wide band running for E734 has been done in the beam we discuss. E734 is an experiment designed to measure elastic scattering of neutrinos and antineutrinos on electrons and protons. The detector is sufficiently large (approx. =170 tons) that enough events can be detected to make precision measurements of cross sections. In particular, the reaction nu/sub ..mu../ + e ..-->.. nu/sub ..mu../ + e has been detected with more than 100 events, requiring a detailed understanding of the beam characteristics for normalization.
Date: February 27, 1985
Creator: White, D. Hywel
Object Type: Report
System: The UNT Digital Library
Liquid to gas leak ratios with liquid nitrogen and liquid helium (open access)

Liquid to gas leak ratios with liquid nitrogen and liquid helium

To predict the leak rates of liquid helium and liquid nitrogen containers at operating conditions we need to know how small leaks (10/sup -8/ to 10/sup -5/ atm-cm/sup 3/ air/s), measured at standard conditions, behave when flooded with these cryogens. Two small leaks were measured at ambient conditions (approx.750 Torr and 295 K), at the normal boiling points of LN/sub 2/ and LHe, and at elevated pressures above the liquids. The ratios of the leak rates of the liquids at ambient pressure to the gases (G) at ambient pressure and room temperature were: GN/sub 2/(1), LN/sub 2/(18), GHe(1), and LHe(172). The leak rate ratio of LN/sub 2/ at elevated pressure was linear with pressure. The leak rate ratio of LHe at elevated pressure was also linear with pressure.
Date: February 26, 1985
Creator: Batzer, T. H. & Call, W. R.
Object Type: Article
System: The UNT Digital Library
Nuclear performance optimization of the Be/Li/Th blanket for the fusion breeder (open access)

Nuclear performance optimization of the Be/Li/Th blanket for the fusion breeder

More rigorous nuclear analysis, including treatment of resonance self-shielding effects coupled with an optimization procedure, has resulted in improved performance of the Be/Li/Th blanket. Net U-233 breeding ratio has increased 36% (to 0.84) while at an average U-233/Th ratio of 0.5 a/o average energy multiplication has increased only 12% (to 2.1) compared with earlier results.
Date: February 26, 1985
Creator: Lee, J. D. & Bandini, B. R.
Object Type: Article
System: The UNT Digital Library
Cryogenic structural materials for superconducting magnets (open access)

Cryogenic structural materials for superconducting magnets

This paper reviews research in the United States and Japan on structural materials for high-field superconducting magnets. Superconducting magnets are used for magnetic fusion energy devices and for accelerators that are used in particle-physics research. The cryogenic structural materials that we review are used for magnet cases and support structures. We expect increased materials requirements in the future.
Date: February 22, 1985
Creator: Dalder, E.N.C. & Morris, J.W. Jr.
Object Type: Article
System: The UNT Digital Library
Elimination of electromagnetic radiation in plasma simulation: the Darwin or magnetoinductive approximation (open access)

Elimination of electromagnetic radiation in plasma simulation: the Darwin or magnetoinductive approximation

For many astrophysical and most magnetic fusion applications, the purely electromagnetic modes generated by real as well as simulation ''plasma'' fluctuations are a source of high frequency radiation that is often irrelevant to the physics of interest. Unfortunately, a numerical CFL stability limit prevents either making c infinite or deltat large while using the usual explicit Maxwell's equations for the fields. A modification of Maxwell's equations, which provides implicitly the field components, circumvents this problem. The solution is to neglect retardation effects so that the electromagnetic propagation speed is effectively infinite. The purely electromagnetic modes in this limit evolve ''instantly'' to a time-asymptotic configuration about the macroscopic plasma configuration at each new time level. The Darwin or magnetoinductive approximation effectively provides infinite propagation speeds for purely electromagnetic modes by converting Maxwell's equations from hyperbolic to elliptic in character. In practice, this is accomplished by neglecting the solenoidal part of the displacement current. The elimination of the CFL time step constraint more than offsets the substantially more complicated field solution that is required. The details of a numerical implementation of this model will be presented. Numerical examples will be given and extentions of the Darwin field solution to other plasma models …
Date: February 21, 1985
Creator: Hewett, D.W.
Object Type: Article
System: The UNT Digital Library
Fireball Ridge Geothermal Prospect, Churchill County, Nevada (open access)

Fireball Ridge Geothermal Prospect, Churchill County, Nevada

None
Date: February 21, 1985
Creator: Desormier, William L.
Object Type: Report
System: The UNT Digital Library
Search for Neutrino Oscillations at the Brookhaven AGS (open access)

Search for Neutrino Oscillations at the Brookhaven AGS

We report on a search for neutrino oscillations of the type nu/sub ..mu../ ..-->.. nu/sub e/ in a detector located an effective distance of 96m from the neutrino source in the wide band neutrino beam at the Brookhaven AGS. No excess of electron events was observed. The resulting upper limit on the strength of the mixing between nu/sub ..mu../ and nu/sub e/ in the case of large mass difference ..delta..m/sup 2/ = absolute value m/sub 1//sup 2/ - m/sub 2//sup 2/ between the neutrino mass eigenstates m/sub 1/ and m/sub 2/ is sin/sup 2/2..cap alpha.. less than or equal to 3.4 x 10/sup -3/ at 90% CL. The corresponding upper limit for small mass difference is ..delta..m/sup 2/sin2..cap alpha.. < 0.43 eV/sup 2/. 9 refs.
Date: February 20, 1985
Creator: Ahrens, L. A.; Aronson, S. H.; Connolly, P. L.; Gibbard, B. G.; Murtagh, M. J.; Murtagh, S. J. et al.
Object Type: Article
System: The UNT Digital Library
Ion Trapping in the Accumulator (open access)

Ion Trapping in the Accumulator

The beam space charge (- for {bar p}'s) will attract positive ions. In the absence of additional fields (clearing electrodes, e.g.) these ions will be trapped in the beam potential well. The depth of this potential well has been calculated for some geometries relevant for the accumulator.
Date: February 18, 1985
Creator: Marriner, J.
Object Type: Report
System: The UNT Digital Library
1 to 2 GeV/c beam line for hypernuclear and kaon research (open access)

1 to 2 GeV/c beam line for hypernuclear and kaon research

A kaon beam line operating in the range from 1.0 to 2.0 GeV/c is proposed. The line is meant for kaon and pion research in a region hitherto inaccessible to experimenters. Topics in hypernuclear and kaon physics of high current interest include the investigation of doubly strange nuclear systems with the K/sup -/,K/sup +/ reaction, searching for dibaryon resonances, hyperon-nucleon interactions, hypernuclear ..gamma.. rays, and associated production of excited hypernuclei. The beam line would provide separated beams of momentum analyzed kaons at intensities greater than 10/sup 6/ particles per spill with a momentum determined to one part in a thousand. This intensity is an order of magnitude greater than that currently available. 63 references.
Date: February 15, 1985
Creator: Chrien, R. E.
Object Type: Report
System: The UNT Digital Library
Integrating quality assurance and research and development (open access)

Integrating quality assurance and research and development

Quality assurance programs cannot be transferred from one organization to another without attention to existing cultures and traditions. Introduction of quality assurance programs constitutes a significant change and represents a significant impact on the organizational structure and operational mode. Quality assurance professionals are change agents, but do not know how to be effective ones. Quality assurance as a body of knowledge and experience can only become accepted when its practitioners become familiar with their role as change agents. 8 references.
Date: February 15, 1985
Creator: Dronkers, J.J.
Object Type: Article
System: The UNT Digital Library
Interaction of the ATA beam with the TM/sub 030/ mode of the accelerating cells (open access)

Interaction of the ATA beam with the TM/sub 030/ mode of the accelerating cells

The interaction of the electron beam in the Advanced Test Accelerator with an azimuthally symmetric mode of the accelerating cells is investigated theoretically. The interaction possibly could cause modulation of the beam current at the resonant frequency of the mode. Values of the shunt impedance and Q value of the mode were obtained from previous measurement and analysis. Lagranian hydrodynamics is employed and a WKB solution to the equation of motion is obtained. Results indicate that the interaction will not be a problem in the accelerator.
Date: February 14, 1985
Creator: Neil, V.K.
Object Type: Report
System: The UNT Digital Library
Multiple time-scale methods in particle simulations of plasmas (open access)

Multiple time-scale methods in particle simulations of plasmas

This paper surveys recent advances in the application of multiple time-scale methods to particle simulation of collective phenomena in plasmas. These methods dramatically improve the efficiency of simulating low-frequency kinetic behavior by allowing the use of a large timestep, while retaining accuracy. The numerical schemes surveyed provide selective damping of unwanted high-frequency waves and preserve numerical stability in a variety of physics models: electrostatic, magneto-inductive, Darwin and fully electromagnetic. The paper reviews hybrid simulation models, the implicitmoment-equation method, the direct implicit method, orbit averaging, and subcycling.
Date: February 14, 1985
Creator: Cohen, B.I.
Object Type: Article
System: The UNT Digital Library
Electrical supply for MFTF-B superconducting magnet system (open access)

Electrical supply for MFTF-B superconducting magnet system

The MFTF-B magnet system consists of 42 superconducting magnets which must operate continuously for long periods of time. The magnet power supply system is designed to meet the operational requirements of accuracy, flexibility, and reliability. The superconducting magnets require a protection system to protect against critical magnet faults of quench, current lead overtemperature, and overcurrent. The protection system is complex because of the large number of magnets, the strong coupling between magnets, and the high reliability requirement. This paper describes the power circuits and the components used in the design.
Date: February 13, 1985
Creator: Shimer, D. W. & Owen, E. W.
Object Type: Article
System: The UNT Digital Library
Electromagnetic Effects in Relativistic Electron Beam Plasma Interactions (open access)

Electromagnetic Effects in Relativistic Electron Beam Plasma Interactions

Electromagnetic effects excited by intense relativistic electron beams in plasmas are investigated using a two-dimensional particle code. The simulations with dense beams show large magnetic fields excited by the Weibel instability as well as sizeable electromagnetic radiation over a significant range of frequencies. The possible relevance of beam plasma instabilities to the laser acceleration of particles is briefly discussed. 6 refs., 4 figs.
Date: February 13, 1985
Creator: Kruer, W. L. & Langdon, A. B.
Object Type: Article
System: The UNT Digital Library
Cryopumping hydrogen isotope mixtures in MFTF-B with and without argon adsorbent (open access)

Cryopumping hydrogen isotope mixtures in MFTF-B with and without argon adsorbent

Mixtures of hydrogen isotopes, primarily deuterium (D/sub 2/), protium-deuterium (HD), and protium (H/sub 2/) must be pumped by the vacuum system in the Mirror Fusion Test Facility at Lawrence Livermore National Laboratory. In this study, we used argon as an adsorbent for cryopumping these isotopes at 4.2 K and found that deuterium will displace already adsorbed protium. Thus, when we pump mixtures of the two, sufficient argon must be supplied to adsorb both species. We also found that without argon, deuterium will cryptrap protium in accord with Raoult's law.
Date: February 12, 1985
Creator: Schumacher, B.J. & Call, W.R.
Object Type: Article
System: The UNT Digital Library
Statistical analyses in the study of solar wind-magnetosphere coupling (open access)

Statistical analyses in the study of solar wind-magnetosphere coupling

Statistical analyses provide a valuable method for establishing initially the existence (or lack of existence) of a relationship between diverse data sets. Statistical methods also allow one to make quantitative assessments of the strengths of observed relationships. This paper reviews the essential techniques and underlying statistical bases for the use of correlative methods in solar wind-magnetosphere coupling studies. Techniques of visual correlation and time-lagged linear cross-correlation analysis are emphasized, but methods of multiple regression, superposed epoch analysis, and linear prediction filtering are also described briefly. The long history of correlation analysis in the area of solar wind-magnetosphere coupling is reviewed with the assessments organized according to data averaging time scales (minutes to years). It is concluded that these statistical methods can be very useful first steps, but that case studies and various advanced analysis methods should be employed to understand fully the average response of the magnetosphere to solar wind input. It is clear that many workers have not always recognized underlying assumptions of statistical methods and thus the significance of correlation results can be in doubt. Long-term averages (greater than or equal to 1 hour) can reveal gross relationships, but only when dealing with high-resolution data (1 to 10 …
Date: February 12, 1985
Creator: Baker, D.N.
Object Type: Article
System: The UNT Digital Library
Beam-Beam Limited Luminosity (open access)

Beam-Beam Limited Luminosity

This report talks about Beam-Beam Limited Luminosity
Date: February 11, 1985
Creator: Hahn, H.
Object Type: Report
System: The UNT Digital Library
Radial implosion acceleration (open access)

Radial implosion acceleration

A scheme to generate high accelerating gradients (approximately (approx.) a few gigaelectronvolts per meter) is described. The acceleration is nonresonant so that staging may be fairly easy, and the energy source is relativistic e-beams so that a relatively high over all efficiency may be achievable.
Date: February 11, 1985
Creator: Channell, P.J.
Object Type: Article
System: The UNT Digital Library
Multivariable current control for electrically and magnetically coupled superconducting magnets (open access)

Multivariable current control for electrically and magnetically coupled superconducting magnets

Superconducting magnet systems under construction and projected for the future contain magnets that are magnetically coupled and electrically connected with shared power supplies. A change in one power supply voltage affects all of the magnet currents. A current controller for these systems must be designed as a multivariable system. The paper describes a method, based on decoupling control, for the rational design of these systems. Dynamic decoupling is achieved by cross-feedback of the measured currents. A network of gains at the input decouples the system statically and eliminates the steady-state error. Errors are then due to component variations. The method has been applied to the magnet system of the MFTF-B, at the Lawrence Livermore National Laboratory.
Date: February 8, 1985
Creator: Owen, E. W. & Shimer, D. W.
Object Type: Article
System: The UNT Digital Library
Multivariable current control for electrically and magnetically coupled superconducting magnets. Revision 1 (open access)

Multivariable current control for electrically and magnetically coupled superconducting magnets. Revision 1

Superconducting magnet systems under construction and projected for the future contain magnets that are magnetically coupled and electrically connected with shared power supplies. A change in one power supply voltage affects all of the magnet currents. A current controller for these system must be designed as a multivariable system. The power describes a method, based on decoupling control, for the rational design of these systems. Dynamic decoupling is achieved by cross-feedback of the measured currents. A network of gains at the input decouples the system statically and eliminates the steady-state error. Errors are then due to component variations. The method has been applied to the magnet system of the MFTF-B, at the Lawrence Livermore National Laboratory.
Date: February 8, 1985
Creator: Owen, E. W. & Shimer, D. W.
Object Type: Article
System: The UNT Digital Library
Utilization of fission reactors for fusion engineering testing (open access)

Utilization of fission reactors for fusion engineering testing

Fission reactors can be used to conduct some of the fusion nuclear engineering tests identified in the FINESSE study. To further define the advantages and disadvantages of fission testing, the technical and programmatic constraints on this type of testing are discussed here. This paper presents and discusses eight key issues affecting fission utilization. Quantitative comparisons with projected fusion operation are made to determine the technical assets and limitations of fission testing. Capabilities of existing fission reactors are summarized and compared with technical needs. Conclusions are then presented on the areas where fission testing can be most useful.
Date: February 8, 1985
Creator: Deis, G. A. & Miller, L. G.
Object Type: Article
System: The UNT Digital Library