Dynamics of angular momentum accumulation in damped nuclear reactions (open access)

Dynamics of angular momentum accumulation in damped nuclear reactions

The dynamical evolution of the correlated angular momentum distribution in a damped nuclear reaction is discussed within the framework of the nucleon exchange transport model. 13 references.
Date: May 1, 1984
Creator: Randrup, J. & Doessing, T.
System: The UNT Digital Library
Logging technology for high-temperature geothermal boreholes (open access)

Logging technology for high-temperature geothermal boreholes

Research in materials, equipment, and instrument development was required in the Hot Dry Rock Energy Extraction Demonstration at Fenton Hill located in northern New Mexico. Results of this extensive development advanced the logging technology in geothermal boreholes to present state-of-the art. The new Phase II Energy Extraction System at the Fenton Hill Test Site will consist of two wellbores drilled to a depth of about 4570 m (15,000 ft) and then connected by a series of hydraulic-induced fractures. The first borehole (EE-2) was completed in May of 1980 at a depth of 4633 m (15,200 ft) of which approximately 3960 m (13,000 ft) is in Precambrian granitic rock. Starting at a depth of approximately 2930 m (9600 ft), the borehole was inclined up to 35/sup 0/ from vertical. Bottom-hole temperature in EE-2 is 320/sup 0/C. The EE-3 borehole was then drilled to a depth of 4236 m (13,900 ft). Its inclined part is positioned directly over the EE-2 wellbore with a vertical separation of about 450 m (1500 ft) between them. Many of the geophysical measurements needed to develop the hot dry rock concept are unique. Most of the routine instruments used in petroleum drilling fail in the hot and …
Date: May 1, 1984
Creator: Dennis, B.R.
System: The UNT Digital Library
Electron cyclotron resonance (ECR) ion sources (open access)

Electron cyclotron resonance (ECR) ion sources

Starting with the pioneering work of R. Geller and his group in Grenoble (France), at least 14 ECR sources have been built and tested during the last five years. Most of those sources have been extremely successful, providing intense, stable and reliable beams of highly charged ions for cyclotron injection or atomic physics research. However, some of the operational features of those sources disagreed with commonly accepted theories on ECR source operation. To explain the observed behavior of actual sources, it was found necessary to refine some of the crude ideas we had about ECR sources. Some of those new propositions are explained, and used to make some extrapolations on the possible future developments in ECR sources.
Date: May 1, 1984
Creator: Jongen, Y.
System: The UNT Digital Library
Workshop on electronic and ionic collision cross sections needed in the modeling of radiation interactions with matter: proceedings (open access)

Workshop on electronic and ionic collision cross sections needed in the modeling of radiation interactions with matter: proceedings

The term modeling in the Workship title refers to the mathematical analysis of the consequences of many collision processes for characterizing the physical stage of radiation actions. It requires as input some knowledge of collision cross sections. Traditionally, work on cross sections and work on the modeling are conducted by separate groups of scientists. It was the purpose of the Workshop to bring these two groups together in a forum that would promote effective communication. Cross-section workers described the status of their work and told what data were available or trustworthy. Modeling workers told what kind of data were needed or were most important. Twenty-two items from the workshop were prepared separately for the data base.
Date: May 1, 1984
Creator: unknown
System: The UNT Digital Library
ASP: a new PEP experiment to measure single photons (open access)

ASP: a new PEP experiment to measure single photons

The design and construction of a new experiment for PEP designed to measure the flux of low energy photons unaccompanied by any additional photons, or charged tracks is described. The device consists of arrays of extruded lead glass bars and PWC's in the central region with lead-scintillator shower counters, drift chambers and PWC's in the forward regions. 9 references.
Date: May 1, 1984
Creator: Hollebeek, R.
System: The UNT Digital Library
Theories of fermion masses (open access)

Theories of fermion masses

We present grand unified theories in which the quark masses and mixing angles are calculated in terms of the lepton masses through simple group theory. The theories contain no small Yukawa couplings. A favored value of the top quark mass is 35 GeV.
Date: May 1, 1984
Creator: Bagger, J.; Dimopoulos, S.; Georgi, H. & Raby, S.
System: The UNT Digital Library
lambda. N effective interaction (open access)

lambda. N effective interaction

A combination of theoretical estimates, based on a ..lambda..N potential model, and phenomenological analysis of hypernuclear data is used to determine a set of four P/sub N/s/sub ..lambda../ two-body matrix elements which characterize the spin dependence of the ..lambda..N interaction in the p shell. The central spin-spin and the ..lambda.. spin-orbit matrix elements are most strongly constrained by existing data. The spin dependence is weak in the sense that s/sub ..lambda../ doublet splittings are predicted to be of order 100 keV except for the special case of /sub ..lambda..//sup 7/Li where the central spin-spin interaction dominates and the ground-state doublet separation is likely to be about 600 keV. The results of recent (K/sup -/, ..pi../sup -/..gamma..) experiments at the Brookhaven AGS are interpreted in terms of the ..lambda..N effective interaction.
Date: May 23, 1984
Creator: Millener, D. J.
System: The UNT Digital Library
Computer control of large accelerators design concepts and methods (open access)

Computer control of large accelerators design concepts and methods

Unlike most of the specialities treated in this volume, control system design is still an art, not a science. These lectures are an attempt to produce a primer for prospective practitioners of this art. A large modern accelerator requires a comprehensive control system for commissioning, machine studies and day-to-day operation. Faced with the requirement to design a control system for such a machine, the control system architect has a bewildering array of technical devices and techniques at his disposal, and it is our aim in the following chapters to lead him through the characteristics of the problems he will have to face and the practical alternatives available for solving them. We emphasize good system architecture using commercially available hardware and software components, but in addition we discuss the actual control strategies which are to be implemented since it is at the point of deciding what facilities shall be available that the complexity of the control system and its cost are implicitly decided. 19 references.
Date: May 1, 1984
Creator: Beck, F. & Gormley, M.
System: The UNT Digital Library
D0 experiment: its trigger, data acquisition, and computers (open access)

D0 experiment: its trigger, data acquisition, and computers

The new collider facility to be built at Fermilab's Tevatron-I D0 region is described. The data acquisition requirements are discussed, as well as the hardware and software triggers designed to meet these needs. An array of MicroVAX computers running VAXELN will filter in parallel (a complete event in each microcomputer) and transmit accepted events via Ethernet to a host. This system, together with its subsequent offline needs, is briefly presented.
Date: May 1, 1984
Creator: Cutts, D.; Zeller, R.; Schamberger, D. & Van Berg, R.
System: The UNT Digital Library
Macroscopic treatment of nuclear dynamics (open access)

Macroscopic treatment of nuclear dynamics

A qualitative classification of nucleus-nucleus reactions into four types is described, a consequence of the existence of up to three milestone configurations that a fusing system may be faced with. These considerations lead to phenomenological formulae for fusion and compound-nucleus cross-sections that may be compared with experiments by the use of rectilinear cross section plots. Examples of more specific model calculations of nuclear reactions employing the Chaotic Regime Dynamics are described. Some misunderstandings regarding the Wall and Wall-and-Window formulae, underlying this type of dynamics, are discussed in the appendix. 23 references.
Date: May 1, 1984
Creator: Swiatecki, W. J.
System: The UNT Digital Library
Induction linacs for heavy ion fusion research (open access)

Induction linacs for heavy ion fusion research

The new features of employing an induction linac as a driver for inertial fusion involve (1) transport of high-current low-emittance heavy ion beams, (2) multiple independently-focussed beams threading the same accelerator structure, and (3) synthesis of voltage waveforms to accomplish beam current amplification. A research program is underway at LBL to develop accelerators that test all these features with the final goal of producing an ion beam capable of heating matter to approx. 70 eV. This paper presents a discussion of some properties of induction linacs and how they may be used for HIF research. Physics designs of the High Temperature Experiment (HTE) and the Multiple Beam Experiment (MBE) accelerators are presented along with initial concepts of the MBE induction units.
Date: May 1, 1984
Creator: Fessenden, T.J.
System: The UNT Digital Library
Upgrade of MFTF-B for fusion technology (open access)

Upgrade of MFTF-B for fusion technology

This report discussses such things as operating scenarios and engineering features of the upgrade. In particular, such things as the magnet system, heating, fueling, drift pumping, halo scraper, direct converter, vacuum pumping, tritium systems, vacuum vessel and support structure, shielding, electrical systems, maintenance, safety and siting, and the operation and test program are described. (MOW)
Date: May 24, 1984
Creator: Thomassen, K. I.; Doggett, J. N.; Logan, B. G. & Nelson, W. D.
System: The UNT Digital Library
Measurements of the a-Dependence of Deep-Inelastic Electron Scattering From Nuclei (open access)

Measurements of the a-Dependence of Deep-Inelastic Electron Scattering From Nuclei

The deep inelastic electron scattering cross sections per nucleon sigma/sub A/ for d, He, Be, C, Al, Ca, Fe, Ag, and Au were measured in kinematic range 0.09 less than or equal to x less than or equal to 0.9 and 2 less than or equal to Q/sup 2/ less than or equal to 15 (GeV/c)/sup 2/ using electrons with energies ranging from 8 to 24.5 GeV. The ratio sigma/sub A//sigma/sub d/ is consistent with unity in the range 0.1 < x < 0.3. For 0.3 < x < 0.8, the ratio decreases logarithmically with atomic weight A, or linearly with average nuclear density. No Q/sup 2/ dependence in the ratio was observed over the kinematic range of the data. This has been interpreted as evidence for a change in the quark momentum distribution in the nucleus due to the presence of 6 quark clusters or a larger nucleon bag size. 13 references.
Date: May 1, 1984
Creator: Arnold, R. G.; Bosted, P. E.; Chang, C. C.; Gomez, J.; Katramatou, A. T.; Petratos, G. G. et al.
System: The UNT Digital Library
LLNL nuclear data libraries used for fusion calculations (open access)

LLNL nuclear data libraries used for fusion calculations

The Physical Data Group of the Computational Physics Division of the Lawrence Livermore National Laboratory has as its principal responsibility the development and maintenance of those data that are related to nuclear reaction processes and are needed for Laboratory programs. Among these are the Magnetic Fusion Energy and the Inertial Confinement Fusion programs. To this end, we have developed and maintain a collection of data files or libraries. These include: files of experimental data of neutron induced reactions; an annotated bibliography of literature related to charged particle induced reactions with light nuclei; and four main libraries of evaluated data. We also maintain files of calculational constants developed from the evaluated libraries for use by Laboratory computer codes. The data used for fusion calculations are usually these calculational constants, but since they are derived by prescribed manipulation of evaluated data this discussion will describe the evaluated libraries.
Date: May 21, 1984
Creator: Howerton, R. J.
System: The UNT Digital Library
Seismic design of low-level nuclear waste repositories and toxic waste management facilities (open access)

Seismic design of low-level nuclear waste repositories and toxic waste management facilities

Identification of the elements of typical hazardous waste facilities (HFWs) that are the major contributors to the risk are focussed on as the elements which require additional considerations in the design and construction of low-level nuclear waste management repositories and HWFs. From a recent study of six typical HWFs it was determined that the factors that contribute most to the human and environmental risk fall into four basic categories: geologic and seismological conditions at each HWF; engineered structures at each HWF; environmental conditions at each HWF; and nature of the material being released. In selecting and carrying out the six case studies, three groups of hazardous waste facilities were examined: generator industries which treat or temporarily store their own wastes; generator facilities which dispose of their own hazardous wastes on site; and industries in the waste treatment and disposal business. The case studies have a diversity of geologic setting, nearby settlement patterns, and environments. Two sites are above a regional aquifer, two are near a bay important to regional fishing, one is in rural hills, and one is in a desert, although not isolated from nearby towns and a groundwater/surface-water system. From the results developed in the study, it was …
Date: May 8, 1984
Creator: Chung, D.H. & Bernreuter, D.L.
System: The UNT Digital Library
Cepheid Evolution (open access)

Cepheid Evolution

A review of the phases of stellar evolution relevant to Cepheid variables of both Types I and II is presented. Type I Cepheids arise as a result of normal post-main sequence evolutionary behavior of many stars in the intermediate to massive range of stellar masses. In contrast, Type II Cepheids generally originate from low-mass stars of low metalicity which are undergoing post core helium-burning evolution. Despite great progress in the past two decades, uncertainties still remain in such areas as how to best model convective overshoot, semiconvection, stellar atmospheres, rotation, and binary evolution as well as uncertainties in important physical parameters such as the nuclear reaction rates, opacity, and mass loss rates. The potential effect of these uncertainties on stellar evolution models is discussed. Finally, comparisons between theoretical predictions and observations of Cepheid variables are presented for a number of cases. The results of these comparisons show both areas of agreement and disagreement with the latter result providing incentive for further research.
Date: May 1, 1984
Creator: Becker, S. A.
System: The UNT Digital Library
Acceleration of polarized protons at the AGS (open access)

Acceleration of polarized protons at the AGS

Spin physics in the past has provided an acid test of many models and theories and over the last decade has revealed new and unexpected phenomena to confront present day theories. This work received great impetus from the experiments at the ZGS, where for the first time multi-GeV polarized beams became available. This, in conjunction with polarized targets, allowed the complete specification of the initial quantum states in high energy proton-proton interactions and led to many startling new results. Although spin effects were important at the previously measured lower energies, practically all theorists felt that spin effects would become negligible at higher energies. Instead, the ZGS results showed in many cases even larger effects than those observed at lower energies. By the time the ZGS was shut down in 1979, high energy polarized proton projects were planned for KEK in Japan, SATURNE in France, and the AGS at Brookhaven. At present, serious thought is being given to high energy polarized proton beams at Fermilab, CERN, and indeed in planning for the Superconducting Super Collider. Today, I would like to describe the facility at Brookhaven and give you the present status of the project. We have been in the commissioning phase …
Date: May 30, 1984
Creator: Ratner, L .G.
System: The UNT Digital Library
Thermochemical data for nuclear waste disposal (open access)

Thermochemical data for nuclear waste disposal

Thermochemical data for nuclear waste disposal are compiled. The resulting data base consists of enthalpy, entropy and heat capacity of formation, and Debye-Huckel coefficients of selected substances for about 25 elements. Values of the data are combined with intrinsic equilibrium constants at 25/sup 0/C and zero ionic strength to calculate equilibrium quotients to 350/sup 0/C and 3 ionic strength. PuSO/sub 4//sup 2 +/, UOH/sup 3 +/ and UO/sub 2/CO/sub 3/(aq) are given as examples.
Date: May 1, 1984
Creator: Phillips, S.L.
System: The UNT Digital Library
Status of beam transport with the ETA and ATA accelerators (open access)

Status of beam transport with the ETA and ATA accelerators

Both the Experimental Test Accelerator (ETA) and the Advanced Test Accelerator (ATA) are 10 kA electron induction linacs. The ETA produces a 4.5 MeV, 30 ns pulse, and the ATA a 50 MeV, 70 ns pulse. The ETA has been operational since 1979, having produced over 6 million pulses. Both the beam breakup instability and lower frequency transverse motions of the beam have been suppressed by accelerator cavity damping and with a wire damping zone. These efforts will be summarized. The ATA has become operational within this last year. Full beam current operation has not yet been achieved because of low-frequency transverse motion and centroid drift of the beam. The beam breakup instability has also been observed but does not disrupt the beam. Efforts at finding the source of the drift and low frequency motion, as well as wire damping of these motions will be reported. 6 references, 6 figures.
Date: May 1, 1984
Creator: Struve, K. W.; Caporaso, G. J.; Chong, Y. P.; Clark, J. C.; Fessenden, T. J.; Lauer, E. J. et al.
System: The UNT Digital Library
Reentry analysis (open access)

Reentry analysis

This paper presents the criteria, previous nuclear experience in space, analysis techniques, and possible breakup enhancement devices applicable to an acceptable SP-100 reentry from space. Reactor operation in nuclear-safe orbit will minimize the radiological risk; the remaining safeguards criteria need to be defined. A simple analytical point mass reentry technique and a more comprehensive analysis method that considers vehicle dynamics and orbit insertion malfunctions are presented. Vehicle trajectory, attitude, and possible breakup enhancement devices will be integrated in the simulation as required to ensure an adequate representation of the reentry process.
Date: May 1, 1984
Creator: Biehl, F.A.
System: The UNT Digital Library
Hadron physics (open access)

Hadron physics

Is all hadronic physics ultimately describable by QCD. Certainly, many disparate phenomena can be understood within the QCD framework. Also certainly, there are important questions which are open, both theoretically (little guidance, as yet) and experimentally, regarding confinement. Are there dibaryons, baryonium, glueballs. In addition, there are experimental results which at present do not have an explanation. This talk, after a short section on QCD successes and difficulties, will emphasize two experimental topics which have recent results - glueball spectroscopy and exclusive reactions at large momentum transfer. Both are experimentally accessible in the AGS/LAMPF II/AGS II/TRIUMF II/SIN II energy domain.
Date: May 30, 1984
Creator: Bunce, G.
System: The UNT Digital Library
Research and development activities in geothermal drilling, completion and logging (open access)

Research and development activities in geothermal drilling, completion and logging

The principal goal in this program is the development of an advanced driling system that can drastically reduce well costs. The program is defined in five basic elements: rock penetration mechanics, fluid technology, borehole mechanics, diagnostics, and permeability enhancement. Each of these elements are briefly summarized with examples of typical projects in each area.
Date: May 1, 1984
Creator: Finger, J.
System: The UNT Digital Library
Heavy ion upgrade of the Bevatron local injector (open access)

Heavy ion upgrade of the Bevatron local injector

A new heavy ion injector system for the Bevatron, consisting of a PIG ion source, an RFQ linac, and two Alvarez linacs, is nearing completion. It will make available to the Bevatron a source of ions up to mass 40 independent of the SuperHILAC, enhancing the operational flexibility of the Bevalac complex. The RFQ accelerator, made operational in mid 1983, accelerates ions with q/A greater than or equal to 0.14 to 200 keV/n. The RFQ is followed by a new 200 MHz Alvarez linac operating in the 2..beta..lambda mode which further accelerates the ions to 800 keV/n. This linac is followed by a foil stripper and a portion of the old injector linac, rebuilt to accelerate beams with q/A greater than or equal to 0.35 to 5 MeV/n in the 2..beta..lambda mode. Details are given of the configuration, equipment modifications, and project status.
Date: May 1, 1984
Creator: Staples, J.; Gough, R.; Abbott, S.; Dwinell, R.; Halliwell, J.; Howard, D. et al.
System: The UNT Digital Library
XIXth Rencontre de Moriond on electroweak interactions and unified theories: summary talk (open access)

XIXth Rencontre de Moriond on electroweak interactions and unified theories: summary talk

Topics discussed at the XIXth Rencontre de Moriond on electroweak interactions and unified theories are briefly discussed. (WHK)
Date: May 1, 1984
Creator: Goldhaber, G.
System: The UNT Digital Library