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Calculations to assist in a new Hiroshima yield estimate. Final report, August 19-December 31, 1983

Description: This report describes calculations and analysis performed in an attempt to provide a new estimate for the yield of the Hiroshima weapon. Newly discovered meteorological data was adapted for use in one- and two-dimensional hydrodynamic codes, and a series of calculations was then run for different values of yield. The objective was to determine what yield produced an overpressure record which could best be correlated with an actual trace measured at a parachute-dropped canister. Altitude of the bomb and canister-carrying aircraft at drop time was also a variable parameter. The analysis provides an estimate of 16.6 + 0.3 kt for the yield of the Hiroshima weapon. A drop altitude of near 35,500 feet is shown to be consistent with the signal time-of-arrival. This yield value is within the range of other estimates, but the drop altitude is higher than that previously assumed to be reasonable.
Date: June 15, 1984
Creator: Kennedy, L.W.; Roth, L.A. & Needham, C.E.
Partner: UNT Libraries Government Documents Department

Study of East Kazakh explosions and propagation in Central Asia using regional Chinese seismograms

Description: Seismograms recorded at the Urumchi Station in northwestern China from eleven Asian events including seven presumed East Kazakh nuclear explosions were analyzed. Group velocity dispersion curves of Rayleigh waves were measured at short periods on paths through basin and fold belt terrains. At 10 sec period, the velocities on paths over sedimentary basins are 25% slower than velocities on paths over fold belts. We interpret those differences in velocities to be due to the great thicknesses of sedimentary deposits in basin terrains. Epicentral locations were estimated using differential travel times between P/sub n/ and L/sub g/ and particle motions of Rayleigh waves measured on a single three-component record. For a 1000 km path, the location errors (one standad deviation) are about +-125 km in azimuth and +-30 km in distance. In addition, systematic errors due to structural effects on surface-wave paths and on velocities of regional phases are shown to seriously bias location estimates of several events. We applied a differential phase method to Rayleigh waves from the East Kazakh explosions and found that signals of all events are in-phase with signals from the reference event on 10/12/80. Thus, there is no evidence for phase reversals or shifts at the Urumchi station in the frequency band where signal to noise ratio is good and where assumptions of the method are valid. Seismic moments of explosions were estimated using models of explosion sources with associated tectonic release. Observed amplitude spectra of Rayleigh waves were richer in high frequencies than predicted by the model. This could be a source effect related to source medium excitation (i.e., Green's functions) or a path effect caused by energy focussing and/or amplifications. We discuss the potential bias in the estimates of moment due to assumptions/limitations. 24 references, 16 figures, 6 tables.
Date: March 1, 1984
Creator: Patton, H.J. & Mills, J.M. Jr.
Partner: UNT Libraries Government Documents Department

Key technological issues in LMFBR high-temperature structural design - the US perspective

Description: The purpose of this paper is: (1) to review the key technological issues in LMFBR high-temperature structural design, particularly as they relate to cost reduction; and (2) to provide an overview of activities sponsored by the US Department of Energy to resolve the issues and to establish stable, standardized, and defensible structural design methods and criteria. Specific areas of discussion include: weldments, structural validation tests, simplified design analysis procedures, design procedures for piping, validation of the methodology for notch-like geometries, improved life assessment procedures, thermal striping, extension of the methodology to new materials, and ASME high-temperature Code reform needs. The perceived problems and needs in each area are discussed, and the current status of related US activities is given.
Date: January 1, 1984
Creator: Corum, J.M.
Partner: UNT Libraries Government Documents Department

Results of calculations of external gamma radiation exposure rates from local fallout and the related radionuclide compositions of two hypothetical 1-MT nuclear bursts. Final report

Description: This report presents data on calculated gamma radiation exposure rates and local surface deposition of related radionuclides resulting from two hypothetical 1-Mt nuclear bursts. Calculations are made of the debris from two types of bombs: one containing /sup 235/U as a fissionable material (designated oralloy), the other containing /sup 238/U (designated tuballoy). 4 references.
Date: December 1, 1984
Creator: Hicks, H.
Partner: UNT Libraries Government Documents Department

Neutron and gamma-ray dose measurements at various distances from the Little Boy replica

Description: We measured neutron and gamma-ray dose rates at various distances from the Little Boy-Comet Critical Assembly at Los Alamos National Laboratory (LANL) in April of 1983. The Little Boy-Comet Assembly is a replica of the atomic weapon detonated over Hiroshima, designed to be operated at various steady-state power levels. The selected distances for measurement ranged from 107 m to 567 m. Gamma-ray measurements were made with a Reuter-Stokes environmental ionization chamber which has a sensitivity of 1.0 ..mu..R/hour. Neutron measurements were made with a pulsed-source remmeter which has a sensitivity of 0.1 ..mu..rem/hour, designed and built at Lawrence Livermore National Laboratory (LLNL). 12 references, 7 figures, 6 tables.
Date: August 1, 1984
Creator: Huntzinger, C.J. & Hankins, D.E.
Partner: UNT Libraries Government Documents Department

Industrial recovery capability. Final report. [Claus alumina catalyst for sulfur production]

Description: This report provides an evaluation of the vulnerability - to a nuclear strike, terrorist attack, or natural disaster - of our national capacity to produce chlorine, beryllium, and a particular specialty alumina catalyst required for the production of sulfur. All of these industries are of critical importance to the United States economy. Other industries that were examined and found not to be particularly vulnerable are medicinal drugs and silicon wafers for electronics. Thus, only the three more vulnerable industries are addressed in this report.
Date: December 1, 1984
Creator: Gregg, D.W.
Partner: UNT Libraries Government Documents Department

Effects of interactive transport and scavenging of smoke on the calculated temperature change resulting from large amounts of smoke

Description: Several theoretical studies with numerical models have shown that substantial land-surface cooling can occur if very large amounts (approx. 100 x 10/sup 12/ = 100 Tg) of highly absorbing sooty-particles are injected high into the troposphere and spread instantaneously around the hemisphere (Turco et al., 1983; Covey et al. 1984; MacCracken, 1983). A preliminary step beyond these initial calculations has been made by interactively coupling the two-layer, three-dimensional Oregon State University general circulation model (GCM) to the three-dimensional GRANTOUR trace species model developed at the Lawrence Livermore National Laboratory. The GCM simulation includes treatment of tropospheric dynamics and thermodynamics and the effect of soot on solar radiation. The GRANTOUR simulation includes treatment of particle transport and scavenging by precipitation, although no satisfactory verification of the scavenging algorithm has yet been possible. We have considered the climatic effects of 150 Tg (i.e., the 100 Mt urban war scenario from Turco et al., 1983) and of 15 Tg of smoke from urban fires over North America and Eurasia. Starting with a perpetual July atmospheric situation, calculation of the climatic effects as 150 Tg of smoke are spread slowly by the winds, rather than instantaneously dispersed as in previous calculations, leads to some regions of greater cooling under the denser parts of the smoke plumes and some regions of less severe cooling where smoke arrival is delayed. As for the previous calculations, mid-latitude decreases of land surface air temperature for the 150 Tg injection are greater than 15/sup 0/C after a few weeks. For a 15 Tg injection, however, cooling of more than several degrees centigrade only occurs in limited regions under the dense smoke plumes present in the first few weeks after the injection. 10 references, 9 figures.
Date: December 1, 1984
Creator: MacCracken, M.C. & Walton, J.J.
Partner: UNT Libraries Government Documents Department

GLODEP2: a computer model for estimating gamma dose due to worldwide fallout of radioactive debris

Description: The GLODEP2 computer code provides estimates of the surface deposition of worldwide radioactivity and the gamma-ray dose to man from intermediate and long-term fallout. The code is based on empirical models derived primarily from injection-deposition experience gained from the US and USSR nuclear tests in 1958. Under the assumption that a nuclear power facility is destroyed and that its debris behaves in the same manner as the radioactive cloud produced by the nuclear weapon that attached the facility, predictions are made for the gamma does from this source of radioactivity. As a comparison study the gamma dose due to the atmospheric nuclear tests from the period of 1951 to 1962 has been computed. The computed and measured values from Grove, UK and Chiba, Japan agree to within a few percent. The global deposition of radioactivity and resultant gamma dose from a hypothetical strategic nuclear exchange between the US and the USSR is reported. Of the assumed 5300 Mton in the exchange, 2031 Mton of radioactive debris is injected in the atmosphere. The highest estimated average whole body total integrated dose over 50 years (assuming no reduction by sheltering or weathering) is 23 rem in the 30 to 50 degree latitude band. If the attack included a 100 GW(e) nuclear power industry as targets in the US, this dose is increased to 84.6 rem. Hotspots due to rainfall could increase these values by factors of 10 to 50.
Date: March 1, 1984
Creator: Edwards, L.L.; Harvey, T.F. & Peterson, K.R.
Partner: UNT Libraries Government Documents Department

Large natural geophysical events: planetary planning

Description: Geological and geophysical data suggest that during the evolution of the earth and its species, that there have been many mass extinctions due to large impacts from comets and large asteroids, and major volcanic events. Today, technology has developed to the stage where we can begin to consider protective measures for the planet. Evidence of the ecological disruption and frequency of these major events is presented. Surveillance and warning systems are most critical to develop wherein sufficient lead times for warnings exist so that appropriate interventions could be designed. The long term research undergirding these warning systems, implementation, and proof testing is rich in opportunities for collaboration for peace.
Date: September 1, 1984
Creator: Knox, J.B. & Smith, J.V.
Partner: UNT Libraries Government Documents Department

Engineering Physics Division progress report, December 31, 1983

Description: Research summaries are given under the following headings: (1) nuclear data, (2) fission reactor research, (3) fusion reactor research, (4) high-energy accelerator shielding and detector research, (5) studies of nuclear weapons effects, (6) energy economics modeling and analysis, (7) analysis of CO/sub 2/ impact on climate, (8) intelligent control system research, and (9) information analysis and distribution. Publications and seminars are listed. (WHK)
Date: March 1, 1984
Creator: Maienschein, F.C.
Partner: UNT Libraries Government Documents Department

Neutron and gamma-ray dose-rates from the Little Boy replica

Description: We report dose-rate information obtained at many locations in the near vicinity of, and at distances out to 0.64 km from, the Little Boy replica while it was operated as a critical assembly. The measurements were made with modified conventional dosimetry instruments that used an Anderson-Braun detector for neutrons and a Geiger-Mueller tube for gamma rays with suitable electronic modules to count particle-induced pulses. Thermoluminescent dosimetry methods provide corroborative data. Our analysis gives estimates of both neutron and gamma-ray relaxation lengths in air for comparison with earlier calculations. We also show the neutron-to-gamma-ray dose ratio as a function of distance from the replica. Current experiments and further data analysis will refine these results. 7 references, 8 figures.
Date: January 1, 1984
Creator: Plassmann, E. A. & Pederson, R. A.
Partner: UNT Libraries Government Documents Department

Isotope and Nuclear Chemistry Division annual report, FY 1983

Description: This report describes progress in the major research and development programs carried out in FY 1983 by the Isotope and Nuclear Chemistry Division. It covers radiochemical diagnostics of weapons tests; weapons radiochemical diagnostics research and development; other unclassified weapons research; stable and radioactive isotope production, separation, and applications (including biomedical applications); element and isotope transport and fixation; actinide and transition metal chemistry; structural chemistry, spectroscopy, and applications; nuclear structure and reactions; irradiation facilities; advanced analytical techniques; development and applications; atmospheric chemistry and transport; and earth and planetary processes.
Date: May 1, 1984
Creator: Heiken, J.H. & Lindberg, H.A. (eds.)
Partner: UNT Libraries Government Documents Department

Fiber optic sensor applications in field testing

Description: Fiber optic sensors (F.O.S.) are defined, and the application of this technology to measuring various phenomonon in diverse and hostile environments are discussed. F.O.S. advantages and disavantages both technically and operationally are summarized. Three sensor techniques - intensity, interferometric, and polarization - are then discussed in some detail. General environmental instrumentation and controls that support the Nuclear Weapons Test Program at the Nevada Test Site are discussed next to provide the reader with a basic understanding of the programmatic task. This will aid in recognizing the various difficulties of the traditional measurement techniques at the NTS and the potential advantages that fiber optic measurement systems can provide. An F.O.S. development program is then outlined, depicting a plan to design and fabricate a prototype sensor to be available for field testing by the end of FY84. We conclude with future plans for further development of F.O.S. to measure more of the desired physical parameters for the Test Program, and to eventually become an integral part of an overall measurement and control system.
Date: April 11, 1984
Creator: Perea, J.A.
Partner: UNT Libraries Government Documents Department

Three-dimensional hydrodynamic hot-spot

Description: The basic processes in the shock initiation of heterogeneous explosives have been investigated theoretically using a model of a cube of nitromethane containing 91 cubic air holes. The interaction of a shock wave with a single air hole and a matrix of air holes in PETN, HMX, and TATB has been numerically modeled. The interaction of a shock wave with the density discontinuities, the resulting hot-spot formation and interaction, and the buildup to propagating detonation were computed using three-dimensional numerical Eulerian hydrodynamics with Arrhenius chemical reaction and accurate equations of state according to the hydrodynamic hot-spot model. The basic processes in the desensitization of a heterogeneous explosive by preshocking with a shock pressure too low to cause propagating detonation was numerically modeled. The basic differences between shock sensitive explosives such as PETN or HMX and shock insensitive explosives such as TATB or NQ may be described using the hydrodynamic hot-spot model.
Date: January 1, 1984
Creator: Mader, C.L.
Partner: UNT Libraries Government Documents Department

Development of a cleaning process for uranium chips machined with a glycol-water-borax coolant

Description: A chip-cleaning process has been developed to remove the new glycol-water-borax coolant from oralloy chips. The process involves storing the freshly cut chips in Freon-TDF until they are cleaned, washing with water, and displacing the water with Freon-TDF. The wash water can be reused many times and still yield clean chips and then be added to the coolant to make up for evaporative losses. The Freon-TDF will be cycled by evaporation. The cleaning facility is currently being designed and should be operational by April 1985.
Date: December 1, 1984
Creator: Taylor, P. A.
Partner: UNT Libraries Government Documents Department

Fire initiation and spread in urban areas due to nuclear attack

Description: Calculation of fire development in urban areas is a critical step in estimating the global effects of nuclear warfare with regard to smoke production and transport. As part of the first phase of a program to improve our ability to calculate fire starts and spread in urban areas, we have performed a parameter sensitivity analysis using the three codes originally developed for civil defense planning by the IIT Research Institute. We have added graphics and made slight improvements to the codes and applied them to the representation of the San Jose urban area used in the Five-City Study of the late 1960s. For a chosen reference attack scenario, we have varied parameters and compared the results to those of a representative baseline case. The parameters varied included: atmospheric visibility, lowest of the various critical ignition energies of window coverings, shading of windows by trees and awnings, extent of blast extinguishment of fires, secondary ignitions, window glass transmittance, specific firebrand generation rate, firebrand distribution range, windspeed, building densities, specific fuel loadings, and window sizes. 13 references, 10 figures, 5 tables.
Date: September 1, 1984
Creator: Reitter, T.A.; Takata, A.N. & Kang, S.W.
Partner: UNT Libraries Government Documents Department

Report of the Long-Range Planning Committee

Description: This is the final report of the Long-Range Planning Committee of the Lawrence Livermore National Laboratory. It describes the make-up, purpose, working assumptions, and activities of the Committee and discusses the work done by the Committee on defense matters, energy, a number of additional topics, and future long-range planning activities.
Date: July 1, 1984
Partner: UNT Libraries Government Documents Department

Neutron and gamma dose and spectra measurements on the Little Boy replica

Description: The radiation-measurement team of the Weapons Engineering Division at Lawrence Livermore National Laboratory (LLNL) measured neutron and gamma dose and spectra on the Little Boy replica at Los Alamos National Laboratory (LANL) in April 1983. This assembly is a replica of the gun-type atomic bomb exploded over Hiroshima in 1945. These measurements support the National Academy of Sciences Program to reassess the radiation doses due to atomic bomb explosions in Japan. Specifically, the following types of information were important: neutron spectra as a function of geometry, gamma to neutron dose ratios out to 1.5 km, and neutron attenuation in the atmosphere. We measured neutron and gamma dose/fission from close-in to a kilometer out, and neutron and gamma spectra at 90 and 30/sup 0/ close-in. This paper describes these measurements and the results. 12 references, 13 figures, 5 tables.
Date: June 1, 1984
Creator: Hoots, S. & Wadsworth, D.
Partner: UNT Libraries Government Documents Department

Neutron spectra as a function of angle at two meters from the Little Boy assembly

Description: Measurements of neutron spectra produced by the Los Alamos National Laboratory (LANL) Little Boy replica assembly (Comet) were made with a combined multisphere and liquid scintillator system, that has been widely used at the Lawrence Livermore National Laboratory. The combined system was used for measurements at the side (90/sup 0/) and nose (0/sup 0/) of the assembly; additional measurements were made at 45/sup 0/ using only the liquid scintillator. Data were obtained at two meters from the center of the reactive region of the assembly, with good agreement between the multisphere and scintillator results. Comparison with liquid scintillator measurements performed by experimenters from the Canadian Defence Research Establishment, Ottawa (DREO) and calculations from LANL depended on the specific angle, obtaining the best agreement at 90/sup 0/. 32 references, 11 figures, 4 tables.
Date: July 2, 1984
Creator: Griffith, R.V.; Huntzinger, C.J. & Thorngate, J.H.
Partner: UNT Libraries Government Documents Department

Fiscal Year 1985 Congressional budget request. Volume 1. Atomic energy defense activities

Description: Contents include: summaries of estimates by appropriation, savings from management initiatives, staffing by subcommittee, staffing appropriation; appropriation language; amounts available for obligation; estimates by major category; program overview; weapons activities; verification and control technology; materials production; defense waste and by-products management; nuclear safeguards and security; security investigations; and naval reactors development.
Date: February 1, 1984
Partner: UNT Libraries Government Documents Department

Little Boy neutron spectrum below 1 MeV

Description: A high-resolution /sup 3/He ionization chamber of the type development by Cuttler and Shalev was used to study the neutron spectrum from the Little Boy mockup. Measurements were made at distances of 0.75 and 2.0 m and at angles of 0/sup 0/, 45/sup 0/, and 90/sup 0/ with respect to the axis of the assembly, which was operated at power levels from 8.6 to 450 mW. Detector efficiency as a function of energy as well as parameters for correction of pulse-height distributions for proton-recoil and wall effects were determined from a set of response functions for monoenergetic neutrons measured at the Los Alamos 3.75-MeV Van de Graaff Accelerator Facility. Pulse-shape discrimination was used to separate /sup 3/He-recoil pulses from the pulse-height distribution. The spectrum was found to be highly structured, with peaks corresponding to minima in the total neutron cross section of iron. In particular, 15% of the neutrons above the epithermal peak in energy were found to be in the 24-keV iron window. Lesser peaks out to 700 keV are also attributable to filtering action of the weapon's heavy iron casing. Data taken using experimental proton-recoil proportional counters are compared with the high-resolution spectra.
Date: January 1, 1984
Creator: Evans, A.E.
Partner: UNT Libraries Government Documents Department

Adjoint transport calculations for sensitivity analysis of the Hiroshima air-over-ground environment

Description: A major effort within the US Dose Reassessment Program is aimed at recalculating the transport of initial nuclear radiation in an air-over-ground environment. This paper is the first report of results from adjoint calculations in the Hiroshima air-over-ground environment. The calculations use a Hiroshima/Nagasaki multi-element ground, ENDF/B-V nuclear data, one-dimensional ANISN flux weighting for neutron and gamma cross sections, a source obtained by two-dimensional hydrodynamic and three-dimensional transport calculations, and best-estimate atmospheric conditions from Japanese sources. 7 references, 2 figures.
Date: January 1, 1984
Creator: Broadhead, B.L.; Cacuci, D.G. & Pace, J.V. III
Partner: UNT Libraries Government Documents Department