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Dose measurements and calculations in the epithermal neutron beam at the Brookhaven Medical Research Reactor (BMRR)

Description: The characteristics of the epithermal neutron beam at BMRR were measured, calculated, and reported. This beam has already been used for animal irradiations. We anticipate that it will be used for clinical trials. Thermal and epithermal neutron flux densities distributions, and dose rate distributions, as a function of depth were measured in a lucite dog-head phantom. Monte Carlo calculations were performed and compared with the measured values. 2 refs., 4 figs., 1 tab.
Date: January 1, 1990
Creator: Fairchild, R. G.; Greenberg, D.; Kamen, Y.; Fiarman, S.; Benary, V.; Kalef-Ezra, J. et al.
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Partner: UNT Libraries Government Documents Department
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US--ITER activation analysis

Description: Activation analysis has been made for the US ITER design. The radioactivity and the decay heat have been calculated, during operation and after shutdown for the two ITER phases, the Physics Phase and the Technology Phase. The Physics Phase operates about 24 full power days (FPDs) at fusion power level of 1100 MW and the Technology Phase has 860 MW fusion power and operates for about 1360 FPDs. The point-wise gamma sources have been calculated everywhere in the reactor at several times after shu… more
Date: September 1, 1990
Creator: Attaya, H.; Gohar, Y. & Smith, D.
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Partner: UNT Libraries Government Documents Department
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Enriched vs non-enriched vs non-fissile targets for pulsed spallation neutron sources

Description: Numerous options exist among alternatives for target material and design of the neutron producing target in pulsed spallation neutron sources. This report surveys the advantages, disadvantages and limitations of some of the alternatives, including discussions of neutron yields, delayed neutron backgrounds, source pulse widths, source-to-moderator coupling, materials performance, fabrication problems, safeguards and security and hazards questions. 5 refs., 5 figs., 2 tabs.
Date: January 1, 1990
Creator: Carpenter, J.M.
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Partner: UNT Libraries Government Documents Department
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Breeding rate measurements in solid fusion blankets with metallic lithium samples

Description: Measurement of the local breeding rate in a large assembly of fusion blanket candidate materials, irradiated by a fusion neutron source, serves the dual purpose of blanket design support and, perhaps more importantly, calculational method and cross section library testing. In this report, we present technical details of a measurement scheme based on deployment of encapsulated lithium metal samples and subsequent thermal digestion of the samples in a metered carrier hydrogen stream, conversion t… more
Date: September 1, 1990
Creator: Porges, K. G. & Bretscher, M. M.
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Partner: UNT Libraries Government Documents Department
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Gamma-ray induced displacement in D20 reactors

Description: Gamma-ray damage to tank walls is typically more severe in D{sub 2}O than in H{sub 2}O moderated lattices because of the much higher ratios of slow-to-fast neutron flux. To estimate this effect it was first necessary to develop energy dependent gamma-ray displacement cross sections for iron. These, along with coupled neutron-gamma-ray transport computations, provided a measure of displacement damage from this source in SRS reactor tank walls. Gamma-ray displacements originating from high energy… more
Date: May 1, 1990
Creator: Baumann, N.P.
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Partner: UNT Libraries Government Documents Department
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Some concluding remarks about cold moderator development

Description: This paper is the transcription of remarks made at the conclusion of the Workshop on Cold Neutron Sources held at the Los Angeles National Laboratory, Los Alamos, New Mexico, March 5--7, 1990. Areas of interest include the following: scattering functions; cold moderator materials; radiation mixing of chemical composition; comparison of some pulsed moderator spectra; hydrogen mixtures; premoderators and shields; composite reflectors; exotic moderator materials; deuterated methanes; mixed moderat… more
Date: January 1, 1990
Creator: Carpenter, J.M.
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Partner: UNT Libraries Government Documents Department
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The role of accelerators in the nuclear fuel cycle

Description: The use of neutrons produced by the medium energy proton accelerator (1 GeV--3 GeV) has considerable potential in reconstructing the nuclear fuel cycle. About 1.5 {approximately} 2.5 ton of fissile material can be produced annually by injecting a 450 MW proton beam directly into fertile materials. A source of neutrons, produced by a proton beam, to supply subcritical reactors could alleviate many of the safety problems associated with critical assemblies, such as positive reactivity coefficient… more
Date: January 1, 1990
Creator: Takahashi, Hiroshi.
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Partner: UNT Libraries Government Documents Department
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The Neutron Radiography Reactor (NRAD)

Description: The Neutron Radiography Reactor (NRAD) operated by Argonne National Laboratory is described in this paper. NRAD was designed to allow radiography of highly absorbing reactor fuel assemblies in the vertical position on the routine basis. 7 figs.
Date: January 1, 1990
Creator: Imel, G.R.; McClellan, G.C. & Pruett, D.P.
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Partner: UNT Libraries Government Documents Department
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Benchmarking report for WIGGLE: A one-dimensional transient diffusion theory code

Description: WIGGLE is a static/transient one-dimensional diffusion theory calculation written to estimate the axial power profile while safety rods are falling during a scram. The code is used in the LOCA Limits Analysis Package (LLAP), a part of the SRS system for calculating thermal-hydraulic limits. Since WIGGLE was designed to be implemented through LLAP and not as a stand-alone code, it consists entirely of subroutines; the problem data must be passed to it from a driver routine. This project concerne… more
Date: November 1, 1990
Creator: Pevey, R.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A prediction of the neutron and charged particle backgrounds in the L detector

Description: Monte Carlo calculations have been made of the neutron flux and activation in the forward and barrel calorimeters in the L* detector and of the neutron flux in the central detector volume. In addition estimates of the charged particle and neutron background rates in the vicinity of the muon chambers has been determined. The Los Alamos National Laboratory code system LAHET and CINDER, 90 along with ISAJET and GEANT were used in these studies. The results indicate that neutron fluences as low as … more
Date: January 1, 1990
Creator: Lee, D.M.; Kinnison, W.W. & Wilson, W.B.
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Partner: UNT Libraries Government Documents Department
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In-situ tritium recovery from Li sub 2 O irradiated in fast neutron flux: BEATRIX-II initial results

Description: The BEATRIX-II experiment in FFTF is an in-situ tritium recovery experiment to evaluate the tritium release characteristics of Li{sub 2}O and its stability under fast neutron irradiation to extended burnups. This experiment includes two specimens: a thin annular specimen capable of temperature transients and a larger temperature gradient specimen. During the first 85 days of the operating cycle of the reactor, the tritium recovery rate of a temperature transient capsule was examined as a functi… more
Date: October 1990
Creator: Kurasawa, T.; Slagle, O. D.; Hollenberg, G. W. & Verrall, R. A.
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Partner: UNT Libraries Government Documents Department
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A Monte Carlo calculation of the neutron flux in the L sup * detector

Description: Monte Carlo calculations have been made of the neutron flux in the forward and barrel calorimeters in the L* detector and of the neutron flux in the central detector volume. In addition estimates of the charged particle and neutron background rates in the vicinity of the muon chambers has been determined. The Los Alamos National Laboratory code system LAHET along with ISAJET and GEANT were used in these studies. The results indicate that neutron influences as low as 2 {times} 10{sup 12} per SSC… more
Date: January 1, 1990
Creator: Lee, D.M.; Kinnison, W.W. & Wilson, W.B.
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Partner: UNT Libraries Government Documents Department
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Application of three-dimensional transport code to the analysis of the neutron streaming experiment

Description: This paper summarized the calculational results of neutron streaming through a Clinch River Breeder Reactor (CRBR) Prototype coolant pipe chaseway. Particular emphasis is placed on results at bends in the chaseway. Calculations were performed with three three-dimensional codes: the discrete ordinates radiation transport code TORT and Monte Carlo radiation transport code MORSE, which were developed by Oak Ridge National Laboratory (ORNL), and the discrete ordinates code ENSEMBLE, which was devel… more
Date: January 1, 1990
Creator: Chatani, K. & Slater, C. O.
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Partner: UNT Libraries Government Documents Department
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Spallation-based science and technology and associated nuclear data requirements

Description: Rapid advances in accelerator technology in recent years promise average proton beam currents as high as 250 mA with energies greater than one GeV. Such an accelerator could produce very high intensities of neutrons and other nuclear particles thus opening up new areas of science and technology. An example is the efficient burning of transuranic and fission product waste. With such a spallation-burner it appears that high-level waste might be converted to low-level waste on a time scale compara… more
Date: January 1, 1990
Creator: Bowman, C. D.; Lisowski, P. W. & Arthur, E. D.
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Partner: UNT Libraries Government Documents Department
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Tensile testing and scanning electron microscope examination of Charpy impact specimens from the HFBR

Description: The Materials Technology Group of the Department of Nuclear Energy (DNE) at Brookhaven National Laboratory (BNL) has performed a fractographic examination of neutron irradiated and unirradiated Charpy V'' notch specimens which have been deformed to failure in a tensile testing apparatus. The evaluation was carried out using a scanning electron microscope (SEM) to evaluate the fracture mode. Photomicrographs were then evaluated to determine if ductile areas were present on the fracture surfaces … more
Date: January 1, 1990
Creator: Czajkowski, C. J.; Schuster, M. H. & Roberts, T. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of a robust model-based reactivity control system

Description: This paper describes the development and implementation of a digital model-based reactivity control system that incorporates a knowledge of the plant physics into the control algorithm to improve system performance. This controller is composed of a model-based module and modified proportional-integral-derivative (PID) module. The model-based module has an estimation component to synthesize unmeasurable process variables that are necessary for the control action computation. These estimated vari… more
Date: January 1, 1990
Creator: Rovere, L. A.; Otaduy, P. J. & Brittain, C. R.
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Partner: UNT Libraries Government Documents Department
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NUFACE: An interface code for the calculation of nuclear responses

Description: The NUFACE interface code computes nuclear responses for use in the nuclear analysis of a given tokamak reactor design. The NUFACE code operates on the neutron and gamma fluxes provided by the one-dimensional neutral-particle transport code ONEDANT. Zonewise and zone-boundary responses are computed to obtain both zone-integrated values and maximum surface values. Information on each material mixture within a zone and on each element or isotope constituent of each material is computed. This feat… more
Date: January 1, 1990
Creator: Henderson, D. L. (Oak Ridge National Lab., TN (USA)) & Gomes, I. C. (Tennessee Univ., Knoxville, TN (USA))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interface-flux nodal transport method

Description: The development of the interface-flux nodal (IFN) method is presented to determine the flux distribution in reactor cells, cores and shielding. The method offers geometric flexibility, high order of spatial expansions of the node-interior sources and the node surface quantities. The surface-integral formulation is reduced to response-matrix-like global equations through coupling coefficients which are generalized expressions for escape and transmission probabilities. The spatial distribution of… more
Date: January 1, 1990
Creator: Kohut, P.
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Partner: UNT Libraries Government Documents Department
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CURE: Clean use of reactor energy

Description: This paper presents the results of a joint Westinghouse Hanford Company (Westinghouse Hanford)-Pacific Northwest Laboratory (PNL) study that considered the feasibility of treating radioactive waste before disposal to reduce the inventory of long-lived radionuclides, making the waste more suitable for geologic disposal. The treatment considered here is one in which waste would be chemically separated so that long-lived radionuclides can be treated using specific processes appropriate for the nuc… more
Date: May 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gamma-Ray and Neutron Leakage Spectra Calculated for Unshieled Reactors

Description: The spectra of neutrons and gamma rays escaping from unshielded reactors have been calculated for a number of simplified cases. Such spectra are important in connection with reactors operating in space orbit around the earth, which would normally have little or no heavy shielding. Reactors in space, such as the Soviet RORSAT spacecraft. Knowledge of the characteristics of their leakage spectra may be useful in understanding or minimizing such interference. The Monte Carlo Neutron-Photon (MCNP) … more
Date: May 1, 1990
Creator: Terrell, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(Reactor dosimetry)

Description: The lead in most aspects of research reactor design and use passed from the USA about 15 years ago, soon after the construction of the HFIR and HFBR. The Europeans have consistently upgraded and improved their existing facilities and have built new ones including the HFR at Grenoble and ORPHEE at Saclay. They studied ultra-high flux concepts ({approximately}10{sup 20}/m{sup {minus}2}{center dot}s{sup {minus}1}) about 10 years ago, and are in the design phase of a new, highly efficient medium fl… more
Date: September 13, 1990
Creator: West, C.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A model for the prediction of Nb sub 3 Sn critical current as a function of field, temperature, strain, and radiation damage

Description: Conductors designed for fusion machines must operate at high fields, under large mechanical loads, and in a high neutron flux. Present designs favor the use of Nb{sub 3}Sn with force-cooling by supercritical helium to extract large nuclear and ac loss heat loads. Consequently, the magnet designer must have a good knowledge of the critical current of the superconductor as a function of field, strain, temperature, and radiation damage. Expanding on work by Hampshire, et al. and Ekin, combined wit… more
Date: September 21, 1990
Creator: Summers, L. T.; Guinan, M. W.; Miller, J. R. & Hahn, P. A.
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Partner: UNT Libraries Government Documents Department
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Neutron beam characterization at the Neutron Radiography Reactor (NRAD)

Description: The Neutron Radiography Reactor (NRAD) is a 250-kW TRIGA Reactor operated by Argonne National Laboratory and is located near Idaho Falls, Idaho. The reactor and its facilities regarding radiography are detailed in another paper at this conference; this paper summarizes neutron flux measurements and calculations that have been performed to better understand and potentially improve the neutronics characteristics of the reactor.
Date: January 1, 1990
Creator: Imel, G.R.; Urbatsch, T.; Pruett, D.P. & Ross, J.R.
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Partner: UNT Libraries Government Documents Department
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Criticality Experiments With Neutron Flux Traps Containing Voids

Description: A research program was initiated for the US Department of Energy (DOE) by the Sandia National Laboratory Transportation Systems Development Department in 1982 to provide benchmark type experimental criticality data in support of the design and safe operations of nuclear fuel transportation systems. The overall objective of the program is to identify and provide the experimental data needed to form a consistent, firm, and complete data base for verifying calculational models used in the critical… more
Date: April 1, 1990
Creator: Bierman, S.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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