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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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Described are preliminary results obtained on a novel gas pressure gauge that operates between 0.1 and 1000 mb. This gauge uses a 1- micron Ci alpha particle source to ionize the gas in a small chamber with an electric field imposed between anode and cathode electrodes that drives positive ions to the cathode where they are collected electronically. This gauge could make Martian pressure measurements.
Angular distributions of elastic and inelastic scattering of 42-MeV alpha particles measured for even tellurium isotopes
Coincidence measurements of absolute cross sections for breakup of deuterons by 42 MeV alpha particles
Blockage of electrically evoked pupillodilation in cat by irradiating hypothalamus with cyclotron- accelerated alpha particles
Radioactive alpha particle density measuring system for atmospheric analyses
Solar proton energy from sept. 3, 1960 flares and alpha particle concentration
Angular distributions measured for elastic and inelastic scattering of 40-MeV alpha particles from even tin isotopes
Thermoluminescent spectra of sodium chloride and hydroxide-free sodium chloride irradiated with 40-mev alpha particles
Quiet time proton and alpha particle flux and differential energy spectra measured by cosmic ray detectors on OGO 3 satellite
Calculations of ionization-excitation source rates in gaseous media irradiated by fission fragments and alpha particles
Low and high linear energy transfer /LET/ cyclotron-accelerated alpha particles effects on Drosophila melanogaster longevity
The results of measurements of scintillation light induced by alpha-particles in high-pressure Xe are presented. The ratio of N(sub ex)/N(sub i) and the intensity and time characteristics of the luminescence signal have been measured for different densities up to 0.74 g/cc. The role and mechanisms of the electron-ion recombination in high-pressure gas have been investigated. The existence of clusters and self-trapped excitons above 0.6 g/cc has been observed and discussed. This work is a part of a development program of high-pressure Xe detectors for low-energy gamma rays.
Distorted-wave born approximation of angular distribution of elastic and inelastic alpha- particle scattering from nuclei at energies above Coulomb barrier
This paper presents solar-flare-associated proton and alpha-particle fluxes determined for major events from October 1972 through March 1987 (the period that represents the last part of solar cycle 20 and the whole of solar cycle 21), using data obtained by detectors on board the IMP-7 and IMP-8 satellites, along with earlier obtained data for cycle 20. It was found that the average omnidirectional flux of protons with kinetic energy above 10 MeV for cycle 21 (64/sq cm per sec) is lower than the corresponding number for cycle 20 (92/sq cm per sec) and for the cycle 19 (378/sq cm per sec). No definitive correlation was found to exist between cycle-averaged solar flare proton fluxes and peak sunspot numbers.
Differential cross sections for inelastic large angle alpha particle scattering from unnatural parity states in Mg showing diffraction pattern
Statistical measurements of solar protons, alpha particles and heavier nuclei by lunar orbiting Explorer 35
Glauber theory can describe elastic scattering of alpha particles by He-4, He-3, H-2, and H-1 at 7 GeV/c if the phase of the nucleon-nucleon elastic-scattering amplitude varies with momentum transfer. The phase variation leads to diffraction patterns differing markedly from those typical of constant-phase calculations and greatly affects the magnitudes of the intensities. These changes are mainly due to changes in the interference between amplitudes for different orders of multiple scattering and to a decrease in their moduli.
A power source that converts a-particle energy into electricity by coulomb collision in doped diamond films is described. Alpha particle decay from curium-244 creates electron-hole pairs by free- ing electrons and holes inside the crystal lattice in N- and P-doped diamond films. Ohmic contacts provide electrical connection to an electronic device. Due to the built-in electric field at the rectifying junction across the hT- and P-doped diamond films, the free electrons are constrained to traveling in generally one direction. This one direction then supplies electrons in a manner similar to that of a battery. The radioactive curium layer may be disposed on diamond films for even distribution of a-particle radiation. The resulting power source may be mounted on a diamond substrate that serves to insulate structures below the diamond substrate from a-particle emission. Additional insulation or isolation may be provided in order to prevent damage from a-particle collision. N-doped silicon may be used instead of N-doped diamond.