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A NOTE ON IMPORTANCE FUNCTIONS FOR THE SHIELDING OF MANNED SPACE VEHICLES

Description: The tissue dose calculations of Kinney were used to calculate several importance functions associated with the dose from primary and secondary particles in the tissue due to penetration of an aluminum shield by a solar-flare proton spectrum. Secondary particles produced in the shield were not considered. (auth)
Date: March 1, 1964
Creator: Alsmiller, R.G. Jr.
Partner: UNT Libraries Government Documents Department

Calculations related to the application of neutrons, protons, negatively charged pions, and heavy ions in cancer radiotherapy

Description: From grantees conference on instrumentation technology; Washington, District of Columbia, USA (26 Sep 1973). The most significant aspects of the research conducted during the period from September 1, 1972 to August 31, 1973 on the comparative study of the use of photons, neutrons, protons, negatively charged pions, and heavy ions in cancer radiotherapy are reviewed. The survival of cultured cells was used as the test criteria. Calculations were made of radiation dose distributions in tissue-equivalent phantoms exposed to charged pions. (CH)
Date: January 1, 1973
Creator: Alsmiller, R.G. Jr.
Partner: UNT Libraries Government Documents Department

DISSOCIATION AND IONIZATION OF H$sub 2$$sup +$ BY ELECTRONS AND PROTONS

Description: <><DSN>16:009503<ABS>Included are summaries of studies of: DCX-1 operation and performance; DCX-2 design and engineering; plasma physics; vacuum arcs; ion production, acceleration, and injection; plasma theory and computations; magnetics; and vacuum system techniques. Separate abstracts were prepared for the eight sections. (B.O.G.) 9504(Faye unscannable abstract)
Date: January 24, 1962
Creator: Alsmiller, R.G. Jr.
Partner: UNT Libraries Government Documents Department

Shielding of fusion reactors

Description: The blanket and shield assemblies of fusion reactors will contain a significant number of very sizable penetrations (neutral beam injection ducts, pumping ports, etc.). The combination of high-energy neutrons and large penetrations will introduce severe design problems that are quite different from those encountered previously. Fusion reactors with their penetrations are very complex geometric structures and in calculating nuclear effects (heating, activation, etc.) tradeoffs must be made between computing efficiency and the accuracy in the geometric modeling. The types of problems that arise due to large penetrations will be illustrated by the calculations that have been carried out to aid in the design of the shielding for the neutral beam injectors of the Tokamak Fusion Test Reactor being built at Princeton University.
Date: January 1, 1979
Creator: Alsmiller, R.G. Jr.
Partner: UNT Libraries Government Documents Department

SPACE VEHICLE SHIELDING STUDIES. PART II. THE ATTENUATION OF SOLAR FLARES BY ALUMINUM SHIELDS

Description: Using the straight-ahead approximation, nucleon-meson cascade calculations were carried out for several solarflare proton spectra incident on a shield. The shield material has approximately the properties of aluminum. Both spherical-shell and slab geometries are considered. (auth)
Date: January 24, 1964
Creator: Alsmiller, R.G. Jr. & Murphy, J.E.
Partner: UNT Libraries Government Documents Department

SPACE VEHICLE SHIELDING STUDIES. CALCULATIONS OF THE ATTENUATION OF A MODEL SOLAR FLARE AND MONOENERGETIC PROTON BEAMS BY ALUMINUM SHIELDS

Description: Using the straight-ahead approximation, nucleon-meson cascade calculations have been carried out for a typical proton flare spectrum incident on a shield and for approximately monoenergetic incident proton beams. The shield material considered has approximately the properties of Al. The results from the monoenergetic beams may be used to obtain shielding information for any incident proton spectrum. (auth)
Date: January 23, 1963
Creator: Alsmiller, R.G. Jr. & Murphy, J.E.
Partner: UNT Libraries Government Documents Department

Energy deposition by 45-GeV photons in H, Be, Al, Cu, and Ta

Description: Electron--photon cascade calculations have been carried out for zero- width beams of 45-GeV photons normally incident on semi-infinite slabs of hydrogen, beryllium, aluminum, copper, and tantalum. The energy deposition is given as a function of both depth and radius in the slabs. (auth)
Date: January 1, 1974
Creator: Alsmiller, R.G. Jr. & Barish, J.
Partner: UNT Libraries Government Documents Department

A PERTURBATION METHOD FOR SOLVING THE ANGLE DEPENDENT NUCLEON-MESON CASCADE EQUATIONS

Description: A method is described for obtaining an approximate solution to the equations describing a nucleon-meson cascade by using the angular dependence of the secondary particle production kernels as a perturbation. The usefulness of the method lies in the fact that in a slab geometry the equations that must be solved numerically are essentially the same as those that are used in the straight-ahead approximation and have been solved previously. (auth)
Date: July 30, 1963
Creator: Alsmiller, R.G. Jr. & Alsmiller, F.S.
Partner: UNT Libraries Government Documents Department

NUCLEON-MESON CASCADE CALCULATIONS: SHIELDING AGAINST AN 800-Mev PROTON BEAM

Description: Nucleon-meson cascade calculations were carried out and the dose as a function of depth was obtained for an 800-Mev proton beam incident on a shield. The physical properties used for the shielding medium are only a rough approximation to the properties of any particular medium. Muon, neutron, pion, and proton dose rates and fluxes are listed. (auth)
Date: February 21, 1963
Creator: Alsmiller, R.G. Jr. & Murphy, J.E.
Partner: UNT Libraries Government Documents Department

Thermodynamics of the fuel fragmentation gas

Description: In the context of nuclear reactor safety studies, a program is in progress at ORNL whereby fuel-fragmentation situations are mocked up by the application of high-current capacitor discharges through solid UO/sub 2/ samples. The goal of the present work is to predict such quantities as the number of gas and liquid fragments and their energy distributions. The point of view adopted is that upon fragmentation, a cloud of UO/sub 2/ vapor is formed containing ''primeval'' liquid fragments which act as condensation centers. In the evolution of time, fragment growth is controlled by nucleation, coagulation and evaporation processes. Eventually, the vapor-droplet system will reach a situation in which clusters (fragments) of various sizes and UO/sub 2/ vapor will coexist in an ''association-disassociation'' equilibrium. Thus, the physical model considered here consists of the identification of the fragmentation gas with an ''imperfect'' vapor, made up of interacting UO/sub 2/ vapor and liquid fragments. The results of the study are presented.
Date: January 1, 1977
Creator: Perez, R.B. & Alsmiller, R.G. Jr.
Partner: UNT Libraries Government Documents Department

Nucleon-meson transport capability for accelerator-breeder target design. [CALOR]

Description: A state-of-the-art code system for nucleon-meson-lepton transport which has direct applicability to accelerator breeders is presented. Some pertinent data that have been obtained using this system are discussed and compared with experimental data.
Date: January 1, 1982
Creator: Gabriel, T.A. & Alsmiller, R.G. Jr.
Partner: UNT Libraries Government Documents Department

Design calculations for the ANS (Advanced Neutron Source) cold source

Description: The calculation procedure, based on discrete ordinates transport methods, that is being used to carry out design calculations for the Advanced Neutron Source cold source is described. Calculated results on the gain in cold neutron flux produced by a liquid deuterium cold source are compared with experimental data and with calculated data previously obtained by P. Ageron et al., at the Institute Max von Laue-Paul Langevin in Grenoble, France. Calculated results are also presented that indicated how the flux of cold neutrons vary with cold source parameters. 23 refs., 5 figs., 3 tabs.
Date: January 1, 1988
Creator: Lillie, R.A. & Alsmiller, R.G. Jr.
Partner: UNT Libraries Government Documents Department

Uncertainties in calculated heating and radiation damage in the toroidal field coil of a tokamak experimental power reactor due to neutron cross-section errors

Description: Calculated results are presented of the uncertainties in the neutron scalar flux, the energy deposition per unit volume, and the displacements per atom in the toroidal field coil of a tokamak experimental power reactor due to neutron cross-section errors in iron and carbon which are major constituents of the blanket-shield-coil configuration considered. The calculations were carried out using perturbation theory to obtain sensitivity profiles for the various cross sections of interest, and these profiles were then combined with cross- section error estimates, including correlations, to obtain the uncertainties. Each of the three responses--the neutron scalar flux, the energy deposition per unit volume, and the displacements per atom--is found to be very sensitive to the cross sections in the energy group which contains the source (approximately 14 MeV since a D-T source is assumed), and each of the responses is found to have a relative standard deviation of approximately 100 percent due to neutron cross- section errors in iron.
Date: March 1, 1976
Creator: Alsmiller, R.G. Jr.; Barish, J. & Weisbin, C.R.
Partner: UNT Libraries Government Documents Department

Nucleon-Meson Cascade Calculations: Transverse Shielding for a 45-Gev Electron Accelerator (Part III)

Description: In two previous reports nucleon-meson cascade calculations were carried out for several cases of interest in the design of the transverse shield for the proposed 45-Bev linear electron accelerator at Stanford University. Results are now given for two additional cases. (auth)
Date: March 28, 1963
Creator: Alsmiller, R. G., Jr.; Alsmiller, F. S. & Murphy, J. E.
Partner: UNT Libraries Government Documents Department

Nuclear design calculations for the TFTR neutral beam injectors

Description: The results of two-dimensional neutronics calculations aimed at identifying the nuclear responses that affect the performance of vital components are summarized. The neutral beam injector assembly was modelled using r-z geometry with cylindrical symmetry about z-axis. The dimensions and compositions of the components were taken from engineering drawings and sketches. The neutron source strength was assumed to be composed entirely of 14-MeV neutrons isotropically emitted from an area having a radius of 70 cm. The total neutron yield from the reactor was 7 x 10/sup 18/ neutrons/second. The radiation transport calculations were performed using the two-dimensional discrete ordinates code DOT with an S/sub 8/ angular quadrature, and a P/sub 3/ Legendre expansion of the cross section. (MHR)
Date: January 1, 1977
Creator: Santoro, R.T.; Alsmiller, R.G. Jr. & Barnes, J.M.
Partner: UNT Libraries Government Documents Department

Design calculations for a neutron collimator for the TFTR

Description: Some of the design calculations for a collimator for TFTR application are presented and discussed. Discrete ordinates transport calculations have been completed for several right circular cylindrical stainless steel collimators using a 14-MeV neutron, isotropic, 30-cm radius disc source to approximate a plasma volume source. The collimators considered in these survey calculations consisted of 3-cm diameter columns centrally located in 60-cm diameter stainless steel cylinders that varied in length from 30 to 180 cm. The source-collimator-detector configurations consisted of the uniform disc source located 60 cm from the entrance of each collimator and a 6-cm diameter 6-cm long right circular cylinder detector located at various distances from the exit of each collimator. The configurations were analyzed with the first collision source code GRTUNCL and the two-dimensional discrete ordinates code DOT III using an S/sub 4/ angular quadrature. (MHR)
Date: January 1, 1977
Creator: Lillie, R.A.; Alsmiller, R.G. Jr. & Mihalczo, J.T.
Partner: UNT Libraries Government Documents Department

Photon dose rate from induced activity in the beam stop of a 400 GeV proton accelerator

Description: Calculated results are presented of the photon dose rate from the induced activity produced in the beam stop of a high-energy proton accelerator. Incident proton energies of 400 GeV, 200 GeV, and 30 GeV are considered. In each case the photon dose rate is given as a function of radius in the beam stop and as a function of time after the beam is turned off for assumed operating times of 90 days and 10 years.
Date: February 1, 1978
Creator: Alsmiller, R.G. Jr.; Gabriel, T.A. & Barish, J.
Partner: UNT Libraries Government Documents Department