Schemes for anti pp interactions at ISABELLE (open access)

Schemes for anti pp interactions at ISABELLE

Various schemes for obtaining anti pp interactions are outlined, and the luminosities obtainable for each case calculated. In the simplest realistic case, a luminosity of 1.3 x 10/sup 29/ is obtained with a 13 hour filling time. The addition of special rf systems in both the AGS and ISABELLE give a scheme with luminosity 8 x 10/sup 29/ in 6 hours. The use of stochastic cooling to stack raises the luminosity to as high as 10/sup 31/ but the filling time is then 68 hours. Finally a scheme is considered that uses a special 30 GeV capture ring. With this, a luminosity of 10/sup 31/ could be achieved after 20 hours, or higher if a larger filling time were acceptable. Further gains could be made if a smaller proton spot on the target is used but a simple calculation suggests that even the spot size assumed may explode the target too fast.
Date: September 8, 1977
Creator: Palmer, Robert B.
System: The UNT Digital Library
Approach to decision modeling for an ignition test reactor (open access)

Approach to decision modeling for an ignition test reactor

A comparison matrix decision model is applied to candidates for a D-T ignition tokamak (TNS), including assessment of semi-quantifiable or judgemental factors as well as quantitative ones. The results show that TNS is mission-sensitive with a choice implied between near-term achievability and reactor technology.
Date: September 30, 1977
Creator: Howland, H.R. & Varljen, T.C.
System: The UNT Digital Library
Planning for the next generation of standard electronics (open access)

Planning for the next generation of standard electronics

Recommendations of a committee for a new standard to meet needs of new high-energy physics experiments are summarized in a nontechnical manner. Existing standards, including CAMAC, were examined; it was felt that none would meet the future needs of high-energy physics. The original committee gave its recommendations and disbanded. The design committee has begun its work; it anticipates finishing in about two years, in time for application of its recommendations to ISABELLE. (RWR)
Date: September 9, 1977
Creator: Leipuner, L.
System: The UNT Digital Library
Techniques for preventing damage to high power laser components (open access)

Techniques for preventing damage to high power laser components

Techniques for preventing damage to components of the LASL Shiva high power laser system were briefly presented. Optical element damage in the disk amplifier from the combined fluence of the primary laser beam and the Xenon flash lamps that pump the cavity was discussed. Assembly and cleaning techniques were described which have improved optical element life by minimizing particulate and optically absorbing film contamination on assembled amplifier structures. A Class-100 vertical flaw clean room used for assembly and inspection of laser components was also described. The life of a disk amplifier was extended from less than 50 shots to 500 shots through application of these assembly and cleaning techniques. (RME)
Date: September 1, 1977
Creator: Stowers, Irving F.; Patton, Howard G.; Jones, Walter A. & Wentworth, Donald E.
System: The UNT Digital Library
Exploding pusher targets for the SHIVA laser system (open access)

Exploding pusher targets for the SHIVA laser system

The first targets for the 20 TW SHIVA laser system were designed. They are simple glass micro-balloons, approximately 300 ..mu..m in diameter and 2 ..mu..m thick, filled with D-T gas. Using LASNEX, whose model physics was utilized successfully for ARGUS targets, we optimize for both gain and yield. The target behaves as an exploding pusher. Different simple analytic models for the physics of this mode are presented, and are tested by comparing their scaling predictions, at constant absorbed power, with those demonstrated by LASNEX. Emphasis is placed on successful prediction of the basic quantities of peak ion temperature and compression, rather than neutron yield or n tau.
Date: September 26, 1977
Creator: Rosen, M. D.; Larsen, J. T. & Nuckolls, J. H.
System: The UNT Digital Library
Polymer concrete patching materials (open access)

Polymer concrete patching materials

The increased use of deicing salts is causing rapid deterioration of portland cement concrete bridge decks. Soluble chlorides cause corrosion of the steel reinforcing rods with a corresponding increase in volume of the rods. This expansion causes stresses in the concrete which result in delaminations and surface spalling. The repair of surface spalls with portland cement concrete can only be made if traffic can be avoided for several days. A patching material which would allow traffic to resume over the repaired area in a few hours was needed. Polymer concrete (PC) was developed to repair deteriorated portland cement concrete. Polymer concrete is defined as a composite material in which the aggregate is bound together in a dense matrix with a polymer binder. The aggregate is mixed with a monomer mixture and subsequently cured in place. Polymer concrete combines the premix characteristics of portland cement concrete with high strength, long term durability properties and fast cure times. PC placed at temperatures between 35/sup 0/F and 95/sup 0/F attains strengths greater than 5000 psi in 2 hours. The high early strength of PC is suitable for use in the repair of highway structures where traffic conditions allow closing of the area for …
Date: September 1, 1977
Creator: Fontana, J.J.
System: The UNT Digital Library
Engineering design solutions of flux swing with structural requirements for ohmic heating solenoids (open access)

Engineering design solutions of flux swing with structural requirements for ohmic heating solenoids

Here a more detailed publication is summarized which presents analytical methods with solutions that describe the structural behavior of ohmic heating solenoids to achieve a better understanding of the relationships between the functional variables that can provide the basis for recommended design improvements. The solutions relate the requirements imposed by structural integrity to the need for producing sufficient flux swing to initiate a plasma current in the tokamak fusion machine. A method is provided to perform a detailed structural analysis of every conducting turn in the radial build of the solenoid, and computer programmed listings for the closed form solutions are made available as part of the reference document. Distinction is made in deriving separate models for the regions of the solenoid where turn-to-turn radial contact is maintained with radial compression or with a bond in the presence of radial tension, and also where there is turn-to-turn radial separation due to the absence or the loss of bonding in the presence of would be radial tension. The derivations follow the theory of elasticity for a body possessing cylindrical anisotropy where the material properties are different in the radial and tangential directions. The formulations are made practical by presenting the methods …
Date: September 30, 1977
Creator: Smith, R. A.
System: The UNT Digital Library
Thermal design and analysis of superconductors for the toroidal field coils of TNS. [NbTi] (open access)

Thermal design and analysis of superconductors for the toroidal field coils of TNS. [NbTi]

The toroidal field coils in two of the four TNS field coil design options are superconducting. NbTi superconductors are used in the low field design option and Nb/sub 3/Sn superconductors are used in the high field design option. The preliminary conceptual design parameters of the coils and the superconductors have been developed. The selected coil shape is the pure tension D-configuration. The superconductors are the multifilamentary, cabled design and are cooled by forced flow supercritical helium. Thermal stability analyses were performed for the superconductors. The cryogenic recovery capability of the NbTi superconductors is more than 10/sup 5/ J/m/sup 3/ of conductor plus helium volume and that of the Nb/sub 3/Sn is more than 3 x 10/sup 5/ j/m/sup 3/.
Date: September 30, 1977
Creator: Lee, A. Y.
System: The UNT Digital Library
Heavy ion scattering in 3D TDHF. [Isodensity contours] (open access)

Heavy ion scattering in 3D TDHF. [Isodensity contours]

Results of three-dimensional (3D) time-dependent Hartree--Fock (TDHF) calculations are presented. The assumptions used in the calculations are summarized. The first reaction considered is /sup 16/O + /sup 16/O at 105 MeV (lab); isodensity contours integrated perpendicular to the reaction plane are shown for several impact parameters as a function of time. Trajectories are also shown, and the kinetics of the reaction is discussed; several other energies were also examined. Most of the deeply inelastic scattering seems to come from small impact parameters. Density contours and trajectories are next shown for /sup 40/Ca + /sup 40/Ca at 278 MeV (lab). Finally, density contours are shown for asymmetric systems: /sup 4/He + /sup 16/O at l = 5 h-bar and 50 MeV (lab) and /sup 16/O + /sup 40/Ca at l = 20, 40, 60, 80 h-bar and 315 MeV (lab). The light fragment seems to maintain the same average number of nucleons with which it started. 25 figures. (RWR)
Date: September 1, 1977
Creator: Weiss, M.S.
System: The UNT Digital Library
Spectra of matrix isolated metal atoms and clusters. [In rare gases] (open access)

Spectra of matrix isolated metal atoms and clusters. [In rare gases]

The matrix isolation spectra of all of the 40 presently known atomic metal species show strong matrix effects. The transition energies are increased, and the bands are broad and exhibit splitting of sublevels which are degenerate in the gas phase. Several models have been proposed for splitting of levels, but basic effects are not yet understood, and spectra cannot be predicted, yet it is possible to correlate gas phase and matrix in many of the systems. Selective production of diatomics and clusters via thermal and optical annealing of atomic species can be monitored by optical spectra, but yields spectroscopically complex systems which, however, especially in the case of transition metals, can be used as precursors in novel chemical reactions. A combination of absorption, emission, ir, Raman, ESR, and other methods is now quickly yielding data which will help correlate the increasing wealth of existing data. 55 references, 6 figures.
Date: September 30, 1977
Creator: Meyer, B.
System: The UNT Digital Library
Performance of Argus as a laser fusion facility (open access)

Performance of Argus as a laser fusion facility

During the fifteen months that the Argus laser facility has been operating we have had two primary goals. These are: (1) to provide focusable, well characterized, high power beams for laser fusion experiments and (2) to further understand the propagation of high power and energy pulses. The propagation experiments have already led to increases in the laser output power and system reliability. Pulses appropriate for advanced targets are shaped to optimize the compression and heating of the target. In general they stress the laser in both limits of energy and power. In this work several results significant to the laser fusion program were realized. The neutron output of fusion targets increased by almost two orders of magnitude to more than 10/sup 9/ neutron/shot. An improved beam propagation technique (image relaying) was developed and partially implemented. It increased the focusable output power for short pulses (30-100 ps) to more than 4.0 TW. More than one kilojoule/beam was extracted from the laser in a high quality beam in a one nanosecond Gaussian pulse. A complex two step optical pulse was generated and successfully amplified to peak powers of more than 3.0 TW. The most recent of the system upgrades are complete image …
Date: September 19, 1977
Creator: Speck, D. R.; Simmons, W. W.; Hunt, J. T.; Boyle, M. J.; Rainer, F.; Storm, E. K. et al.
System: The UNT Digital Library
Energy calibration scheme for acoustic emission (open access)

Energy calibration scheme for acoustic emission

The calibration technique described is an attempt to determine the actual energy release from the events causing emission bursts in beryllium and to quantitatively evaluate the effects of specimen geometry on the apparent energy per burst. (GHT)
Date: September 13, 1977
Creator: Adams, R. O. & Heiple, C. R.
System: The UNT Digital Library
Stability of space-charge neutralized beams (open access)

Stability of space-charge neutralized beams

Consideration is given to the stability of negative ion beams which are neutralized through ionization of a background gas. Two types of instabilities are examined. First, beam-plasma instabilities are analyzed with the dispersion relation showing that they are unimportant if the beam velocity is less than the electron thermal velocity. Second, results of a computer simulation on the flow of a cylindrical beam and the resulting background plasma show that when the background neutral gas density is less than or approximately equal to a critical density as instability occurs. This critical density is the density that would be needed to space-charge neutralize the beam if the positive ions were not retarded by the beam. An approximate dispersion relation indicates that the nature of the instability is a transverse positive-ion acoustic wave which couples to the beam.
Date: September 22, 1977
Creator: Turnbull, R. J. & Hooper, E. B. Jr.
System: The UNT Digital Library
Use of x-ray imaging on laser fusion experiments (open access)

Use of x-ray imaging on laser fusion experiments

A variety of x-ray imaging techniques have been used to study the absorption, transport and implosion characteristics of exploding pusher microsphere targets irradiated with 1.06 ..mu..m light. Multichannel grazing incidence reflection microscopy, zone plate coded imaging and spatially resolved x-ray spectroscopy have observed the thermal and suprathermal x-ray emission associated with these phenomena. A second generation of x-ray imaging devices, designed for forthcoming high density implosion experiments, including axisymmetric x-ray microscopes and 1- and 2-D crystal line imaging devices, will also be briefly discussed.
Date: September 19, 1977
Creator: Boyle, M. J.; Attwood, D. T.; Ceglio, N. M.; Koppel, L. N.; Slivinsky, V. W.; Larsen, J. T. et al.
System: The UNT Digital Library
Comparison of density estimators. [Estimation of probability density functions] (open access)

Comparison of density estimators. [Estimation of probability density functions]

Recent work in the field of probability density estimation has included the introduction of some new methods, such as the polynomial and spline methods and the nearest neighbor method, and the study of asymptotic properties in depth. This earlier work is summarized here. In addition, the computational complexity of the various algorithms is analyzed, as are some simulations. The object is to compare the performance of the various methods in small samples and their sensitivity to change in their parameters, and to attempt to discover at what point a sample is so small that density estimation can no longer be worthwhile. (RWR)
Date: September 1, 1977
Creator: Kao, S. & Monahan, J.F.
System: The UNT Digital Library
40-kV, 25-ms neutral-beam power supply for TMX (open access)

40-kV, 25-ms neutral-beam power supply for TMX

Modifications are described to upgrade the neutral-beam power supply for the TMX from 40 kV, 10 ms to 40 kV, 25 ms. The redesign of the accel and suppressor power supplies to achieve separation of the high-voltage and control sections, operation of the arc pulse lines in series, operation of the arc pulse lines in a noisy environment with SCR trigger and crowbar, and modifications to the electrolytic storage banks are discussed.
Date: September 23, 1977
Creator: Leavitt, G.A.
System: The UNT Digital Library
Stable propagation of an electron beam in gas (open access)

Stable propagation of an electron beam in gas

Conditions for the stable propagation of a pinched electron beam in low pressure gas (p approximately 0.1 to 100 torr) are described. The observed window of good propagation around p approximately 2 torr air is interpreted as the quenching of the two-stream mode by sufficiently high plasma density and collision frequency, and the simultaneous suppression of the resistive hose mode by sufficiently rapid generation of electrical conductivity from breakdown ionization.
Date: September 30, 1977
Creator: Lee, E. P.; Chambers, F. W.; Lodestro, L. L. & Yu, S. S.
System: The UNT Digital Library
Poloidal field coil design for a fusion--fission breeder reactor (open access)

Poloidal field coil design for a fusion--fission breeder reactor

The magnetic, structural, and thermal design of superconducting poloidal field coils for a tokamak fusion-fission breeder reactor are described. The design requirements and considerations, with the resulting parameters, are presented.
Date: September 30, 1977
Creator: Howland, H. R.; Kelly, J .L. & Chi, J. W. H.
System: The UNT Digital Library
Technology of mirror machines: LLL facilities for magnetic mirror fusion experiments (open access)

Technology of mirror machines: LLL facilities for magnetic mirror fusion experiments

Significant progress in plasma confinement and temperature has been achieved in the 2XIIB facility at Livermore. These encouraging results, and their theoretical corroboration, have provided a firm basis for the design of a new generation of magnetic mirror experiments, adding support to the mirror concept of a fusion reactor. Two new mirror experiments have been proposed to succeed the currently operating 2XIIB facility. The first of these called TMX (Tandem Mirror Experiment) has been approved and is currently under construction. TMX is designed to utilize the intrinsic positive plasma potential of two strong, and relatively small, minimum B mirror cells to enhance the confinement of a much larger, magnetically weaker, centrally-located mirror cell. The second facility, MFTF (Mirror Fusion Test Facility), is currently in preliminary design with line item approval anticipated for FY 78. MFTF is designed primarily to exploit the experimental and theoretical results derived from 2XIIB. Beyond that, MFTF will develop the technology for the transition from the present small mirror experiments to large steady-state devices such as the mirror FERF/FTR. The sheer magnitude of the plasma volume, magnetic field, neutral beam power, and vacuum pumping capacity, particularly in the case of MFTF, has placed new and exciting …
Date: September 15, 1977
Creator: Batzer, T. H.
System: The UNT Digital Library
Small-angle neutron scattering from voids in neutron irradiated type 304 stainless steel. [E > 0. 1 MeV] (open access)

Small-angle neutron scattering from voids in neutron irradiated type 304 stainless steel. [E > 0. 1 MeV]

Preliminary small-angle neutron scattering results designed to investigate the structure of voids in neutron-irradiated polycrystalline annealed type 304 stainless steel were obtained. Specimens were subjected to irradiation at 400/sup 0/C to a fluence of 1.6 x 10/sup 23/ n/cm/sup 2/ (E > 0.1 MeV). Void interference effects were seen for voids having an average diameter of about 290 A. The distribution was ''gas-like''with an exclusion distance of 307 A. 1 figure, 1 table. (RWR)
Date: September 1, 1977
Creator: Child, H.R. & Spooner, S.
System: The UNT Digital Library
Impurity and gas throughput control for TNS (open access)

Impurity and gas throughput control for TNS

A model of the interaction between an ignited plasma and a wall is utilized to study the impact of impurities and recycled fuel ions and helium ash on the burn time of the plasma. The model indicates that the impurity concentration, n/sub im/, grows exponentially toward a maximum value determined by the confinement time for impurities, tau/sub im/, the sputtering coefficient, S/sub i/, and the isolation coefficient, ..cap alpha... The time for n/sub im/ to reach a critical value and quench the plasma was determined for representative impurities, C, Mo, W, Fe, under various conditions of plasma temperature. Methods for extending the burn time by minimizing the effective sputtering coefficient of the wall and increasing the isolation of the plasma from the wall are reviewed. The carbides, B/sub 4/C and SiC, are found to have encouraging sputtering properties but their thermal, chemical and mechanical properties need to be evaluated before they can be recommended for use as first walls. The magnetic divertor is the preferred isolation scheme. Because the divertor carries impurities and leaked fuel and helium ions to a burial chamber, required pumping speeds are found to be very high for TNS plasmas and supplemental particle trapping systems must …
Date: September 30, 1977
Creator: Sucov, E. W.
System: The UNT Digital Library
Optical design considerations for laser fusion reactors (open access)

Optical design considerations for laser fusion reactors

The plan for the development of commercial inertial confinement fusion (ICF) power plants is discussed, emphasizing the utilization of the unique features of laser fusion to arrive at conceptual designs for reactors and optical systems which minimize the need for advanced materials and techniques requiring expensive test facilities. A conceptual design for a liquid lithium fall reactor is described which successfully deals with the hostile x-ray and neutron environment and promises to last the 30 year plant lifetime. Schemes for protecting the final focusing optics are described which are both compatible with this reactor system and show promise of surviving a full year in order to minimize costly downtime. Damage mechanisms and protection techniques are discussed, and a recommendation is made for a high f-number metal mirror final focusing system.
Date: September 1, 1977
Creator: Monsler, M.J. & Maniscalco, J.A.
System: The UNT Digital Library
Compact 80-keV neutral-beam module (open access)

Compact 80-keV neutral-beam module

A compact and maintainable source of 80-keV neutral beams that focus to a high power density is required for the Mirror Fusion Test Facility (MFTF). In the new source being designed and built to meet these requirements, the cross-sectional area is reduced in two ways: by immersing the source in a vacuum where high voltage can be held over smaller distances and by redesigning grid supporting structures. Reliability is increased by reducing the electric fields everywhere else below those present between grids and by design innovations. The latter include techniques to reduce stray magnetic field and disperse gas uniformly, all metal-ceramic construction, and a 60-kV shield enclosing all 80-kV electrodes. Wherever possible, we have attempted to simplify the construction. We expect to solve problems that arise during testing either with add-on fixes or with the techniques already tested successfully on the Lawrence Berkeley Laboratory (LBL) 120-keV source. Easy maintenance is obtained by a compact isolation valve and by modular construction. Curving both the grid wires and their holders provides focusing in two planes.
Date: September 29, 1977
Creator: Molvik, A. W.; Baird, E. D.; Berkner, K. H.; Cooper, W. S.; Duffy, T. J.; Ehlers, K. W. et al.
System: The UNT Digital Library
Catalyzed combustion in a flat plate boundary layer. II. Numerical calculations (open access)

Catalyzed combustion in a flat plate boundary layer. II. Numerical calculations

A computer program has been developed to solve the boundary layer equations for laminar flow over a heated plate with H/sub 2//air combustion. The objectives are to investigate the importance of homogeneous as opposed to catalytic surface reactions during the combustion process, and to determine the roles of heat and mass transfer and their effect on combustion. Results are presented for combustion of H/sub 2//air at an equivalence ratio of 0.1 for flow over a noncatalytic plate at a surface temperature of 1100/sup 0/K. A detailed mechanism involving 8 chemical species and 13 reactions has been used to describe the kinetics. The reactions leading to the initiation of combustion and the effect of the large diffusivity of hydrogen are discussed. The boundary conditions for catalytic surface and a simplified model to account for catalytic wall reaction are formulated. Results are presented for combustion over a catalytic surface and compared with the non-catalytic case.
Date: September 1, 1977
Creator: Schefer, R. & Robben, F.
System: The UNT Digital Library