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Safeguards Effectiveness Evaluations in Safeguards Planning

Description: This paper describes analytic tools we developed to quantify the effectiveness of safeguards against theft of special nuclear material by insiders. These tools help identify vulnerabilities in existing safeguards, suggest potential improvements, and help assess the benefits of these upgrades prior to implementation. Alone, these tools are not sufficient for safeguards planning, since the cost of implementing all suggested upgrades almost always exceeds the available resources. This paper descri… more
Date: December 3, 1987
Creator: Al-Ayat, R. A.
Partner: UNT Libraries Government Documents Department
open access

An ion beam simulation of the swelling of U/sub 3/Si

Description: Uranium intermetallics are under consideration as possible low-enrichment reactor fuels. These materials divide into two classes with regard to dimensional stability during their service lifetime: those which suffer extreme dimensional growth and those which do not. It has been suggested that the rapid-swelling materials are those that become glassy under irradiation while the low-swelling materials are those that remain crystalline. The structural and dimensional stabilities of U/sub 3/Si (dep… more
Date: December 1, 1987
Creator: Allen, C. W.; Birtcher, R. C.; Rehn, L. E. & Hofman, G. L.
Partner: UNT Libraries Government Documents Department
open access

Heavy leptons at the SSC

Description: It is argued that detection of heavy leptons at the Superconducting Super Collider seems to be very difficult but perhaps not impossible. The feasibility is shown to depend critically upon the ability to identify events with W's decaying hadronically and missing transverse momentum. (LEW)
Date: December 15, 1987
Creator: Anderson, G. & Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
open access

Extension of nuclear structure data base searches for gamma-ray laser candidates

Description: Results from a data base search of computerized nuclear structure libraries have been extended and augmented so as to expand the information available for nuclei suitable as gamma-ray laser candidates. The spectrum of nuclear levels occurring in deformed rotational nuclei have been calculated and have been used in conjunction with isomeric state data for odd-A systems. The results of this augmentation effort are presented with particular emphasis on results obtained for /sup 177/Lu, /sup 177/Hf… more
Date: December 1, 1987
Creator: Arthur, E. D.; Madland, D. G. & George, D. C.
Partner: UNT Libraries Government Documents Department
open access

Dynamics and Structure of Energetic Displacement Cascades

Description: This paper summarizes recent progress in the understanding of energetic displacement cascades and the primary state of damage in metals. On the theoretical side, the availability of supercomputers has greatly enhanced our ability to simulate cascades by molecular dynamics. Recent application of this simulation technique to Cu and Ni provides new insight into the dynamics of cascade processes. On the experimental side, new data on ion beam mixing and in situ electron microscopy studies of ion da… more
Date: December 1, 1987
Creator: Averback, R. S.; Diaz de la Rubia, T. & Benedek, R.
Partner: UNT Libraries Government Documents Department
open access

The performance of actinide-containing SRL 165 type glass in unsaturated conditions

Description: As part of the effort by the Nevada Nuclear Waste Storage Investigations (NNWSI) Project to evaluate the volcanic tuff beds of Yucca Mountain, Nevada, as a repository for the permanent storage of high-level nuclear waste, the interaction of actinide-doped Savannah River Laboratory (SRL) 165 type glass with the unsaturated repository environment has been studied. The NNWSI Unsaturated Test method has been used, and the results from batch and continuous tests completed through 18 months demonstra… more
Date: December 31, 1987
Creator: Bates, J.K. & Gerding, T.J.
Partner: UNT Libraries Government Documents Department
open access

Nuclear excitation via the motion of electrons in a strong laser field

Description: A method of switching from a nuclear isomeric state to a lasing state is examined. A semi-classical model of laser-electron-nuclear coupling is developed. In it the electrons are treated as free in the external field of the laser, but with initial conditions corresponding to their atomic orbits. Application is made to testing this model in /sup 235/U and to the design criteria of a gamma-ray laser. 14 refs., 2 tabs.
Date: December 1, 1987
Creator: Berger, J. F.; Gogny, D. & Weiss, M. S.
Partner: UNT Libraries Government Documents Department
open access

A short vademecum on CP violation in heavy flavor decays

Description: A short introduction into the phenomenology of CP asymmetries in beauty (and D/sup 0/) decays is given. Different experimental environments are briefly compared and some semiquantitative estimates listed.
Date: December 1, 1987
Creator: Bigi, I. I.
Partner: UNT Libraries Government Documents Department
open access

Non multa, sed multum: Future lessons from two-prong, two-body decays of beauty

Description: There are four two-body, two-prong decays modes of B mesons and two for beauty baryons and they are quite rare, i.e., their branching ratios are not expected to exceed the script O(10/sup -4/) level. Yet a detailed study of their relative rates with a sensitivity level of 10/sup -5/ can yield unique and important information on strong interactions. If the evolution of these reactions in proper time can be traced then, under favorable conditions, one can analyze B/sup 0/ - anti B/sup 0/ mixing a… more
Date: December 1, 1987
Creator: Bigi, I. I. & Stech, B.
Partner: UNT Libraries Government Documents Department
open access

Fabrication and evaluation of transmissive multilayer optics for 8 keV x rays. [Zone plates]

Description: We have investigated an alternative technique for fabricating zone plates that operate in the 5 to 10 keV regime. Ultimately we plan to make zone plates by sputtering alternating layers of opaque and transparent materials onto a thin wire core, then slicing perpendicular to the core axis to produce many zone plates. This technique shows promise for making x-ray optical elements that can be used in industrial crystallography, microprobe and radiography equipment. In a previous publication we rep… more
Date: December 1, 1987
Creator: Bionta, R. M.; Jankowski, Alan Frederic & Makowiecki, D. M.
Partner: UNT Libraries Government Documents Department
open access

The coordination cluster theory for metallic solutions

Description: The coordination cluster theory for the thermodynamic properties of a dilute solute in a binary or higher order solvent. Although the CCT has been applied to liquids, it can be modified for solids. The theory permits one to describe the thermodynamic properties of a solute in a binary solvent in terms of the solute properties in the pure solvent components, the properties of the binary mixture and one unknown parameter. In principle, the properties of solutes in multicomponent solvents can be c… more
Date: December 1, 1987
Creator: Blander, M. & Saboungi, M.L.
Partner: UNT Libraries Government Documents Department
open access

Prompt Processes in Heavy Ion Reactions

Description: We test a relaxation model based on two body nucleon-nucleon scattering processes to interpret phenomena observed in heavy ion reactions. We use the Boltzmann Master Equation to accomplish this. By assuming that the projectile nucleons partition the total excitation with equal a-priori probability of all configurations, we are able to reproduce several sets of neutron spectra from /sup 20/Ne and /sup 12/C induced reactions on /sup 165/Ho and from reactions of /sup 40/Ar or /sup 40/Ca. We point … more
Date: December 1, 1987
Creator: Blann, M. & Remington, B. A.
Partner: UNT Libraries Government Documents Department
open access

Recent results for Mark III

Description: This paper presents recent results from the Mark III detector at SPEAR, in the open charm sector. The first topic discussed is the reanalysis of the direct measurement of the D hadronic branching fractions, where a detailed study has been made of the Cabibbo suppressed and multi-..pi../sup 0/'s D decays backgrounds in the double tag sample. Next, the Dalitz plot analysis of the D decays to K..pi pi.. is presented, leading to the relative fractions of three-body versus pseudoscalarvector decays.… more
Date: December 1, 1987
Creator: Brient, J.C.
Partner: UNT Libraries Government Documents Department
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The role of intestinal injury in hematopoietic gamma ray mortality

Description: Leukemia patients typically have low granulocyte counts as do those with aplastic anemia. A review of the literature on these latter patients quickly indicates that they live much longer than leukemic patients with the same counts. To check this numerically, the survival times for 12 aplastic anemia patients reported in 1934 were compared with the expected survival times for more recent patients using methods employed to compute the probabilities. On the average, the aplastic anemia patients li… more
Date: December 1, 1987
Creator: Broyles, A. A.
Partner: UNT Libraries Government Documents Department
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Detecting the Heavy Higgs Boson at the SSC

Description: Detection of a heavy Higgs boson (2M/sub z/ < M/sub H/ < 1 TeV) is considered. The production mechanisms and backgrounds are discussed. Their implementation in the PYTHIA and ISAJET Monte Carlo programs are checked. The decay modes H ..-->.. ZZ ..-->.. llll and H ..-->.. ZZ ..-->.. llvv are discussed in detail. The signal/background is evaluated and some relevant detector parameters are specified. Some remarks are also made concerning the requirements imposed on detectors by the decay mode H ..… more
Date: December 18, 1987
Creator: Cahn, R. N.; Chanowitz, M.; Golden, M.; Herrero, M. J.; Hinchliffe, I.; Wang, E. M. et al.
Partner: UNT Libraries Government Documents Department
open access

Simulation of effects of redox and precipitation on diffusion of uranium solution species in backfill

Description: This investigation addresses the problem of prediction of the rate of migration of redox-sensitive solution species within packing and backfill materials under conditions of variable oxidation potential. Effects of changes of oxidation potential and precipitation of stable uranium compounds during diffusion of uranium from a region of high oxidation potential into a region of low oxidation potential were simulated numerically. Questions of particular interest addressed in the investigation were… more
Date: December 1, 1987
Creator: Carnahan, C.L.
Partner: UNT Libraries Government Documents Department
open access

Some effects of data base variations on numerical simulations of uranium migration

Description: Numerical simulations of migration of chemicals in the geosphere depend on knowledge of identities of chemical species and on values of chemical equilibrium constants supplied to the simulators. In this work, some effects of variability in assumed speciation and in equilibrium constants were examined, using migration of uranium as an example. Various simulations were done of uranium migration in systems with varying oxidation potential, pH, and mator component content. A simulation including fo… more
Date: December 1, 1987
Creator: Carnahan, C.L.
Partner: UNT Libraries Government Documents Department
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Absolute rate measurements of two-photon process of gases, liquids, and solids

Description: Due to rapid improvements in high-power laser performance, two-photon absorption processes have become a very useful tool for studying the molecular structures of various gases, liquids and solids. However, measurements of absolute two-photon absorption cross sections were more or less ignored previously because of their small size. In this work, we obtained not only the two-photon absorption spectra, but also measurements of their absolute cross sections for various gases, liquids, and solids.… more
Date: December 1, 1987
Creator: Chen, C.H.; McCann, M.P. & Payne, M.G.
Partner: UNT Libraries Government Documents Department
open access

TEM (transmission electron microscopy), APFIM (atom-probe field ion microscopy), and SANS (small-angle neutron scattering) examination of aged duplex stainless steel components from some decommissioned reactors

Description: The present investigation indicates that the primary embrittlement processes of the CF-8 grade cast stainless steel components during extended reactor service are spinodal decomposition of the ferrite phase and M/sub 23/C/sub 6/ carbide precipitation on the austenite-ferrite boundaries. The ferrite hardness measured for the Shippingport reactor valves appears to reflect the different extent of spinodal decomposition among the different valves which contain slightly different Cr contents. G-phas… more
Date: December 1, 1987
Creator: Chung, H. M. & Chopra, O. K.
Partner: UNT Libraries Government Documents Department
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Magnetic and inertial fusion status and development plans

Description: Controlled fusion, pursued by investigators in both the magnetic and inertial confinement research programs, continues to be a strong candidate as an intrinsically safe and virtually inexhaustible long-term energy source. We describe the status of magnetic and inertial confinement fusion in terms of the accomplishments made by the research programs for each concept. The improvement in plasma parameters (most frequently discussed in terms of the Tn tau product of ion temperature, T, density, n, … more
Date: December 4, 1987
Creator: Correll, D. & Storm, E.
Partner: UNT Libraries Government Documents Department
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Cermet-fueled reactors for advanced space applications

Description: Cermet-fueled nuclear reactors are attractive candidates for high-performance advanced space power systems. The cermet consists of a hexagonal matrix of a refractory metal and a ceramic fuel, with multiple tubular flow channels. The high performance characteristics of the fuel matrix come from its high strength at elevated temperatures and its high thermal conductivity. The cermet fuel concept evolved in the 1960s with the objective of developing a reactor design that could be used for a wide r… more
Date: December 1, 1987
Creator: Cowan, C. L.; Palmer, R. S.; Taylor, I. N.; Vaidyanathan, S.; Bhattacharyya, S. K. & Barner, J. O.
Partner: UNT Libraries Government Documents Department
open access

Heavy quark production in ep collisions at HERA. [None]

Description: There are substantial production rates of heavy quarks from ep collisions at HERA. The center of mass energy of about 300 GeV is well above any b-quark threshold effects, and for b/bar b/ production, the cross section is estimated to be 3.3 nb per event, leading to rates approaching 10/sup 6/ b mesons per year. The rates for c/bar c/ production are about two orders of magnitude greater. Two major detectors are under construction and a program of heavy quark physics will start in 1990. 3 refs., … more
Date: December 22, 1987
Creator: Derrick, M.
Partner: UNT Libraries Government Documents Department
open access

Soft x-ray laser microscopy

Description: Microscopes based on soft X-ray lasers possess unique advantages in bridging the gap between high resolution electron microscopy of dehydrated, stained cells and light microscopy at comparatively low resolution of unaltered live cells. The high brightness and short pulse duration of soft X-ray lasers make them ideal for flash imaging of live specimens. The Princeton soft X-ray laser is based on a magnetically confined laser produced carbon plasma. Radiation cooling after the laser pulse produce… more
Date: December 31, 1987
Creator: DiCicco, D.; Meixler, L.; Skinner, C. H.; Suckewer, S.; Hirschberg, J. & Kohen, E.
Partner: UNT Libraries Government Documents Department
open access

CDF (Collider Detector at Fermilab) detector simulation

Description: The Collider Detector at Fermilab (CDF) uses several different simulation programs, each tuned for specific applications. The programs rely heavily on the extensive test beam data that CDF has accumulated. Sophisticated shower parameterizations are used, yielding enormous gains in speed over full cascade programs. 3 refs., 5 figs.
Date: December 1, 1987
Creator: Freeman, J.
Partner: UNT Libraries Government Documents Department
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