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Hyperon and hypernuclear physics with intense beams (open access)

Hyperon and hypernuclear physics with intense beams

A brief examination of progress in the study of hypernuclear physics and the hyperon-nucleon interaction is presented. The use of ..lambda..-hypernuclei in the study of conventional (nonstrange) nuclei is explored. The status of the hyperon-nucleon force problem is reviewed. Anecdotal results are discussed for baryon numbers 4 and 13. ..sigma..-hypernuclei are discussed. Production of S = -2 hypernuclei is mentioned.
Date: January 1, 1983
Creator: Gibson, B. F.
System: The UNT Digital Library
Shape reactivity effects it the rod ejection accident. [PWR] (open access)

Shape reactivity effects it the rod ejection accident. [PWR]

Detailed three-dimensional MEKIN-B calculations of the PWR control rod ejection accident (REA) are being performed as part of the BNL/NRC evaluation of methods currently used to analyze PWR REA events. A principal objective of these calculations has been to evaluate in three dimensions the effect of flux redistribution on the core transient reactivity and hence on transient core power level.
Date: January 1, 1983
Creator: Neogy, P. & Carew, J.F.
System: The UNT Digital Library
Enhancement to the Tektronix PLOT-10 Terminal Control System for creation of graphics metafiles (open access)

Enhancement to the Tektronix PLOT-10 Terminal Control System for creation of graphics metafiles

Many data handling and analysis codes at the Oak Ridge National Laboratory (ORNL) use the Tektronix PLOT-10 Terminal Control System to graphically display data upon Tektronix or Tektronix-emulating graphics devices. Prior to the development of the software libraries and postprocessors discussed within this report, ORNL users were limited to the type of hardcopy output obtainable from the Tektronix PLOT-10 software library. Only Tektronix graphics devices are supported by the PLOT-10 library. The graphics library presented here eliminates this restriction by implementing a suite of software that optionally creates a graphics metafile within the user's disk area while simultaneously drawing a display image on the screen of a user's Tektronix terminal. This graphics metafile can then be postprocessed onto any of the graphics devices at ORNL via the ORNL PLOT command.
Date: January 1, 1983
Creator: Gray, W.H.
System: The UNT Digital Library
Modeling the behavior of the computer-assisted instruction user (open access)

Modeling the behavior of the computer-assisted instruction user

The field of computer-assisted instruction CAI contains abundant studies on effectiveness of particular programs or systems. However, the nature of the field is such that the computer is the focus of research, not the users. Few research studies have focused on the behavior of the individual CAI user. Morgan (1981) stated that descriptive studies are needed to clarify what the important phenomena of user behavior are. The need for such studies is particularly acute in computer-assisted instruction. Building a behavioral model would enable us to understand problem-solving strategies and rules applied by the user during a CAI experience. Also, courseware developers could use this information to design tutoring systems that are more responsive to individual differences than our present CAI is. This paper proposes a naturalistic model for evaluating both affective and cognitive characteristics of the CAI user. It begins with a discussion of features of user behavior, followed by a description of evaluation methodology that can lead to modeling user behavior. The paper concludes with a discussion of how implementation of this model can contribute to the fields of CAI and cognitive psychology.
Date: January 1, 1983
Creator: Stoddard, M.L.
System: The UNT Digital Library
National rf technology research and development program plan (open access)

National rf technology research and development program plan

This plan was prepared by the Oak Ridge National Laboratory at the request of the Office of Fusion Energy, Division of Development and Technology, to define the technology development needs and priorities. The US rf research and development community, with a wide representation from universities, laboratories and industries, participated in many discussions, meetings and in a three-day workshop in developing the needs and priorities definition. This very active and effective involvement of the rf leaders from all of these groups was an essential feature of the activity and results in the plan representing a broad consensus from the magnetic fusion energy development community. In addition, a number of scientists from Japan and Europe participated by providing data.
Date: May 1, 1983
Creator: unknown
System: The UNT Digital Library
Wire Transport Code (open access)

Wire Transport Code

The Wire Transport Code was developed to study the dynamics of relativistic-electron-beam propagation in the transport tube in which a wire-conditioning zone is present. In order for the beam to propagate successfully in the transport section it must be matched onto the wire by focusing elements. The beam must then be controlled by strong lenses as it exits the wire zone. The wire transport code was developed to model this process in substantial detail. It is able to treat axially symmetric problems as well as those in which the beam is transversely displaced from the axis of the transport tube. The focusing effects of foils and various beamline lenses are included in the calculations.
Date: March 1, 1983
Creator: Caporaso, G.J. & Cole, A.G.
System: The UNT Digital Library
Current measurements by Faraday rotation in single-mode fibers (open access)

Current measurements by Faraday rotation in single-mode fibers

We have measured currents in the several-hundred-kiloamp range, with tens-of-nanoseconds risetime, in magnetic fusion devices using simple polarimetric techniques.
Date: January 1, 1983
Creator: Chandler, G.I. & Jahoda, F.C.
System: The UNT Digital Library
Scaling of laser-plasma interactions with laser wavelength and plasma size (open access)

Scaling of laser-plasma interactions with laser wavelength and plasma size

Plasma size is an important parameter in wavelength-scaling experiments because it determines both the threshold and potential gain for a variety of laser-plasma instabilities. Most experiments to date have of necessity produced relatively small plasmas, due to laser energy and pulse-length limitations. We have discussed in detail three recent Livermore experiments which had large enough plasmas that some instability thresholds were exceeded or approached. Our evidence for Raman scatter, filamentation, and the two-plasmon decay instability needs to be confirmed in experiments which measure several instability signatures simultaneously, and which produce more quantitative information about the local density and temperature profiles than we have today.
Date: January 25, 1983
Creator: Max, C. E.; Campbell, E. M.; Mead, W. C.; Kruer, W. L.; Phillion, D. W.; Turner, R. E. et al.
System: The UNT Digital Library
Mechanical features of the ATS RFQ linear accelerator (open access)

Mechanical features of the ATS RFQ linear accelerator

A radio-frequency quadrupole (RFQ) linear accelerator has been constructed and placed in operation on the Los Alamos National Laboratory accelerator test stand (ATS). This accelerator uses an evacuated rf manifold to distribute rf excitation from the 425-MHz rf power supply to the slot-coupled, RFQ vane-cavity, resonator assembly. The RFQ vanes are supported on commercially available copper-plated, linear, resilient C-seals to provide a high-conductivity rf contact that permits aligning and positioning the vanes during tuning, and demounting the vanes for evaluation and modification as necessary. All rf structures are fabricated from stress-relieved, bright-acid copper-plated carbon steel. Measurements made on the accelerator as assembled have demonstrated >8000 vane-cavity Q at the quadrupole's approx. 423.400-MHz accelerating-mode frequency. Operating manifold vacuum of 3 to 6 x 10/sup -8/ torr has been observed after rf conditioning; conditioning required 150 h for stable high-power rf operation. Experience to date has indicated the desirability of modifying the vane rf-contact seat configuration to improve assembly and alignment procedures, improving vane-machining processes to increase vane straightness, installing periodic vane-shorting rings to minimize the effect of dipole modes in the quadrupole accelerating structure,and modifying the waveguide-coupling slot in the manifold to improve forward rf power flow.
Date: January 1, 1983
Creator: Wilson, N.G.; Hayward, T.D. & Lind, G.W.
System: The UNT Digital Library
Low-coupling impedance double-helix structure for use in a ferrite kicker magnet (open access)

Low-coupling impedance double-helix structure for use in a ferrite kicker magnet

In a machine such as the CBA, the ejection ferrite kicker magnet has a very large longitudinal and transverse coupling impedance which could destroy the beam. Using a double-helix structure that surrounds the beam, the beam-induced fields are confined within the helix and, therefore, decoupled from the kicker; but at the same time the helix is transparent to the external fields of the kicker. At first, this may seem paradoxical that the helix is opaque to the fields generated inside the structure by the beam and simultaneously transparent to the external fields generated by the kicker.
Date: January 1, 1983
Creator: Giordano, S.
System: The UNT Digital Library
Dynamic parameter array system (DPA) (open access)

Dynamic parameter array system (DPA)

This paper describes software which provides a means of sharing data among tasks and of accessing and altering dynamically the values of parameters in an executing task. The parameters reside in an RSX-11M memory management region or a VMS global section. The data may be accessed and altered by any task attaching the region. An interactive task is described which allows the user read/write access to the parameters from the keyboard. Keyboard commands can be used to make a disk file copy of values in the region, to initialize the values from a disk file, to examine and modify values, and to define synonyms for parameters. User-callable subroutines which create, attach, and map the region are also described.
Date: January 1, 1983
Creator: Anderson, G.T.; Oothoudt, M.A.; Harrison, J.F. & Kozlowski, T.
System: The UNT Digital Library
Internal trim coils for CBA superconducting magnets (open access)

Internal trim coils for CBA superconducting magnets

In order to correct iron saturation effects and shape the beam working line, superconducting trim coils have been constructed, which operate inside the main coils. Detailed studies of mechanical properties, quench behavior, fields produced, and hysteresis have lead to the production of accelerator-quality coils generating the required-strength harmonics up to cos (7theta). These are routinely installed in CBA main magnets and operate at 80% of short sample with negligible training in an ambient field of more than 5.3T.
Date: January 1, 1983
Creator: Thompson, P.A.; Aronson, S.; Cottingham, J.G.; Garber, M.; Hahn, H. & Sampson, W.B.
System: The UNT Digital Library
Lattice design and tolerance analysis of the CBA transport line (open access)

Lattice design and tolerance analysis of the CBA transport line

The beam transport line from the AGS to CBA is 600 m long and consists of 70 bending magnets and 20 quadrupoles, as well as several special injection components. The beam has to bend 117/sup 0/ horizontally and drop 1.8 m in elevation. To insure that it has momentum acceptance of ..delta..P/P = +-1% and the transverse emittance dilution is within 30%, a detailed tolerance analysis has been carried out on the requirements of the AGS beam properties, magnetic field quality of the transport magnets, and misalignment errors. Field quality tolerances of ..delta..B/sub 0//B less than or equal to 1 x 10/sup -3/ for bending field, ..delta.. G/G less than or equal to 5 x 10/sup -3/ for gradient field, and ..delta..B/sub 2//B less than or equal to 2.5 x 10/sup -4/ cm/sup -2/ of the sextupole components in the bending magnets are indicated.
Date: January 1, 1983
Creator: Weng, W. T.
System: The UNT Digital Library
Overview and direction in the tandem mirror program (open access)

Overview and direction in the tandem mirror program

There are two main thrusts to the tandem mirror program at the present time. One is to gather the experimental data base to verify the axicell thermal-barrier concept and the other to improve the end plugs for tandems. With such improvements one might approach the ideal fusion reactor, a simple solenoid of modular elements whose ends are but a modest perturbation on the configuration from both a cost and technological viewpoint. Progress toward these two goals is discussed here, and the directions to be taken in the immediate future are described.
Date: April 1, 1983
Creator: Thomassen, K.I.
System: The UNT Digital Library
Effect of oxidizing atmosphere on strength loss in HTGR graphites (open access)

Effect of oxidizing atmosphere on strength loss in HTGR graphites

Earlier studies at Brookhaven have shown a greater total-strength loss for the same mass loss in samples of PGX graphite oxidized in O/sub 2//N/sub 2/ or air, versus H/sub 2/O/He or CO/sub 2//He. Similar studies involving H-451 and IG-11 graphites failed to reveal any effect of oxidant type on strength loss. Evidence gathered via photomicroscopy and x-ray mapping (Fe raster scans) support the cause of this phenomenon as being the differences in the microstructural attack by non-catalytic oxidation versus catalytic oxidation. In this paper, further studies involving various reactor-grade graphites and the possible mechanisms leading to strength-loss differences will be discussed.
Date: January 1, 1983
Creator: Heiser, J. H.; Lee, B. S. & Finfrock, C. C.
System: The UNT Digital Library
MFTF-. cap alpha. +T end plug magnet design (open access)

MFTF-. cap alpha. +T end plug magnet design

The conceptual design of the end-plug magnets for MFTF-..cap alpha..+T is described. MFTF-..cap alpha..+ T is a near-term upgrade of MFTF-B, which features new end plugs to improve performance. The Fusion Engineering Design Center has performed the engineering design of MFTF-..cap alpha..+T under the overall direction of Lawrence Livermore National Laboratory. Each end plug consists of two Yin-Yang pairs, each with approx.2.5:1 mirror ratio and approx.5-T peak field on axis; two transition coils; and a recircularizing solenoid. This paper describes the end-plug magnet system functional requirements and presents a conceptual design that meets them. The peak field at the windings of the end-plug coils is approx.6-T. These coils are designed using the NbTi MFTF-B conductor and cooled by a 4.2K liquid helium bath. All the end-plug magnets are designed to operate in the cryostable mode with adequate quench protection for safety. Shielding requirements are stated and a summary of heat loads is provided. Field and force calculations are discussed. The field on axis is shown to meet the functional requirements. Force resultants are reported in terms of winding running loads and resultant coil forces are also given. The magnet structural support is described. A trade study to determine the optimum …
Date: January 1, 1983
Creator: Srivastava, V.C. & O'Toole, J.A.
System: The UNT Digital Library
Design of a versatile ESQ transport system (open access)

Design of a versatile ESQ transport system

A versatile precision beam transport channel was built with inexpensive parts requiring minimum precision machining. The critical items, an optical bench and sliding bases are commercially available standard items. The only important precision machining is illustrated, where a small section of an optical bench is used as a quadrupole assembly holding fixture. With this type of fixturing there is no loss of precision during the transfer of the quadrupole assembly from the EDM setup onto the final assembly, other than the manufacturer-specified mounting and dismounting tolerance. Displacement measurements of the pole tips taken on ten different quadrupole assemblies determined that RMS displacement in the x direction was .000307 and in the y direction was .000290. The actual performance of this system will be presented in other papers at this conference by A.W. Maschke and E.F. Meier.
Date: January 1, 1983
Creator: Brodowski, J.
System: The UNT Digital Library
Acceleration of heavy ions in the AGS (open access)

Acceleration of heavy ions in the AGS

It is possible to use the Brookhaven AGS as a heavy ion machine by adding a cyclotron to the Tandem and using this combination as injector. An intermediate step for lighter ions might consist of injecting the Tandem beam directly into the AGS. In either case, quite high intensities should be possible.
Date: January 1, 1983
Creator: Barton, M. Q.
System: The UNT Digital Library
Solution to the transverse-phase-space time-dependence problem with LAMPF's high-intensity H/sup +/ beam (open access)

Solution to the transverse-phase-space time-dependence problem with LAMPF's high-intensity H/sup +/ beam

The 750 keV H/sup +/ beam at LAMPF has a transverse phase-space time-dependent transient during the first 200 ..mu..s of each 750-..mu..s-long macro-pulse. The time dependence is documented in an earlier report. Further studies indicate that the time dependence is due to space-charge neutralization resulting from secondary emission of electrons produced by collisions of the H/sup +/ and H/sub 2//sup +/ beams on the transport walls. One of several possible solutions has been tested and has proven successful in eliminating the time dependence of the beam entering the linac.
Date: January 1, 1983
Creator: Hurd, J.W.
System: The UNT Digital Library
Muons and Electrons in General (open access)

Muons and Electrons in General

We address the problem of simultaneously identifying electrons and muons in a general-purpose detector at a luminosity of 10/sup 33/ cm/sup -2/sec/sup -1/. Those discoveries and important measurements which are reasonably well predicted now are under way and likely to be fairly complete before turn on. The signatures of new effects to be found at high rates are not well predicted, and for flexibility it may be necessary to look simultaneously for some combination of jets, missing E/sub T/, electrons, and muons. This leads immediately to an open geometry with magnetic tracking and calorimetry. At high luminosity, getting out trigger informtion quickly is a prime concern. Note that if a given signature requires isolating individual events then even for an optimistic integration time of 20 ns, the optimal luminosity is about 2x10/sup 32/cm/sup -2/sec/sup -1/. We have not had the opportunity to be very specific in design or to consider the extended momentum range implied by 10 to 20 TeV collisions.
Date: January 1, 1983
Creator: Nodulman, L. & Bensinger, J.
System: The UNT Digital Library
Overview of fiber radiation effects testing at the Los Alamos National Laboratory (open access)

Overview of fiber radiation effects testing at the Los Alamos National Laboratory

Fiber optics offer potential benefits in diagnostic measurements associated with nuclear testing. Such applications require that optical fibers be located in close proximity to a nuclear test and provide a reliable data transmission path during exposure to intense radiation. The Los Alamos effort has thus concentrated on measurement and understanding of radiation effects in optical fibers at very short times (< 100 ns) after (and during) irradiation. This is in contrast to most other studies that concentrate on times of interest in military, nuclear power, or standard telecommunication applications (1 ms to years). The Los Alamos program has included laboratory tests with intense electron pulse facilities (Febetron 705 and 706) and a fast pulsed electron linac (located at EG and G, Inc. in Santa Barbara, California). In addition, several measurements have been conducted on nuclear tests and some of that data has been released in unclassified publications. This program has used fibers for many data transmission applications. Fibers have also been used as signal transducers by utilizing radiation-to-light conversion processes within the fiber. Past, present, and future activities in this program are discussed.
Date: January 1, 1983
Creator: Lyons, P. B.
System: The UNT Digital Library
Geothermal versus conventional drilling (open access)

Geothermal versus conventional drilling

The procedure for drilling, completing, and logging a geothermal well is outlined. The areas which differ from conventional oil and gas methods are pointed out. (MHR)
Date: January 1, 1983
Creator: Kelsey, J.R.
System: The UNT Digital Library
Recent developments at BNL (open access)

Recent developments at BNL

Topics of interest to the Saturne program, including the status of the polarized beam project, and the accumulator/booster ring, are discussed. The status of the colliding beam accelerator (CBA) is covered. (GHT)
Date: January 1, 1983
Creator: Ratner, L. G.
System: The UNT Digital Library
Response of austenitic steels to radiation damage (open access)

Response of austenitic steels to radiation damage

Austenitic stainless steels are prominent contenders as first wall and blanket structural materials for early fusion power reactors. Properties affecting the performance of this class of alloys in the fusion irradiation environment, such as swelling, tensile elongation, irradiation creep, fatigue, and crack growth, have been identified. These properties and the effects of neutron irradiation on them are discussed in this paper. Emphasis is placed on the present status of understanding of irradiation effects.
Date: January 1, 1983
Creator: Rowcliffe, A.F. & Grossbeck, M.L.
System: The UNT Digital Library