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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Radiation induced visual phosphenes observed by dark adapted human subjects in fast neutron, X ray and positive pion beams at Berkeley comparative to primary cosmic ray effects
Multiple starlike flashes and short streaks reported by subjects exposed to neutrons under 25 mev, discussing interaction with retinal rods by proton recoils
Proton recoil measurements of PuBe neutron source spectra, using pressurized hydrogen spherical proportional counter and liquid scintillator measurements
Neutron emission yield during Pu 238 alpha particles interactions with O 18, taking into account recoil Ne isotopes
Surface and subsurface water analysis on moon and planets by combination neutron experiment using epithermal die-away measurements of hydrogen
Fast neutron spectra in lead and water shielded reactor, comparing liquid scintillator measurements with discrete ordinates code calculations
Proposed model with with neutrons as energy source for solar corona, discussing validity based on capture gamma ray flux expectation
Neutron star models, discussing crystalline crust, particle superfluid properties, rotational vortices and relation to Crab Nebula pulsar
Nuclear forces effects on maximum mass limit of neutron stars models using V gamma type potentials
Vacuum package with Ti bulk sublimator/ion pump combination for 150 kv neutron generator tritium decontamination
Apollo 12 lunar rocks and fines under high energy neutron activation analysis, determining O, Si, Al, Mg and Fe abundances
Cosmic ray exposure ages and rare gas concentration profiles in Apollo 12 lunar rocks, discussing spallation products and neutron capture effects
Solar coronal heating neutron theory based on solar gamma ray flux considerations
Electron microscopy has been used to observe the distribution and morphology of lattice defects introduced into lithium-doped silicon solar cells by neutron irradiation. Upon etching the surface of the solar cells after irradiation, crater-like defects are observed that are thought to be associated with the space charge region around vacancy clusters. Thermal annealing experiments showed that the crater defects were stable in the temperature range 300 to 1200 K in all of the lithium-doped samples. Some annealing of the crater defects was observed to occur in the undoped cells which were irradiated at the lowest doses.
A description of the FASTER-III program for Monte Carlo Carlo calculation of photon and neutron transport in complex geometries is presented. Major revisions include the capability of calculating minimum weight shield configurations for primary and secondary radiation and optimal importance sampling parameters. The program description includes a users manual describing the preparation of input data cards, the printout from a sample problem including the data card images, definitions of Fortran variables, the program logic, and the control cards required to run on the IBM 7094, IBM 360, UNIVAC 1108 and CDC 6600 computers.
Monte Carlo calculations have been carried out to determine the absorbed dose and dose equivalent for 592-MeV protons incident on a cylindrical phantom and for neutrons from 580-MeV proton-Be collisions incident on a semi-infinite phantom. For both configurations, the calculated depth dependence of the absorbed dose is in good agreement with experimental data.
The application of nuclear models to the calculation of neutron capture and inelastic scattering gamma yields is discussed. The gamma ray cascade model describes the cascade process in terms of parameters which either: (1) embody statistical assumptions regarding electric and magnetic multipole transition strengths, level densities, and spin and parity distributions or (2) are fixed by experiment such as measured energies, spin and parity values, and transition probabilities for low lying states.
The effects of fission neutrons and of X-rays on the mouse zygote are discussed. Seven-week-old virgin mice were allowed a 12-hour mating opportunity beginning at 7:00 P.M. Between 1:30 and 4:00 P.M., except where indicated otherwise, the females which had mated (vaginal plug) during the night were either irradiated or sham-irradiated. At the time of irradiation the zygotes were in a pronuclear stage. Sixteen days later the mice were killed and the uteri dissected. The number of dead embryos, live embryos, and gross anomalies were determined. Dead embryos were classified as to stage of development.