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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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Differential spectra of charge components of primary cosmic ray heavy nuclei at different solar modulation levels and effects of interstellar propagation
Intensity and spectra of cosmic ray electrons and positrons in determining mean confinement time, density and solar modulation
Source spectra and composition of galactic cosmic rays implied by analysis of interstellar and interplanetary travel, noting solar modulation
Differential energy spectrum of primary cosmic ray electrons measured on IMP 3 during minimum solar modulation for galactic radiation
Cosmic ray electron flux in 17-63 Mev energy range measured with altitude balloons, noting galactic cosmic ray electrons origin and solar modulation
Primary cosmic ray energy spectra and charge composition during 1965 solar modulation minimum, using scintillator photomultiplier detector on OGO 1
Cosmic ray differential energy spectrum and chemical abundance of elements from lithium to fluorine near minimum solar modulation measured by IMP 3
Long term variations of primary cosmic ray electron flux density from balloon-borne counter telescope data, noting absence of solar modulation
Cosmic ray Li, Be and B nuclei measurements, analyzing differential energy spectra, L-M ratio, atmospheric and solar modulation
Cosmic ray negatron and positron spectra using balloon-borne magnetic spectrometer, obtaining absolute solar modulation of positron flux
Cosmic ray electron energy spectrum and intensity measurements indicating time variations attributed to solar modulation effects
Differential energy spectra of cosmic ray negatrons and positrons, and solar modulation effects on cosmic ray electrons
Quiet time intensity increases and long term solar modulation of interplanetary low energy electrons, using IMP observations
Cosmic ray positrons and negatrons differential energy spectra and solar modulation, using balloon-borne magnetic spectrometer
Cosmic ray positrons and negatrons differential intensities near north geomagnetic pole from balloon flight measurements, noting solar modulation effects
The expected frequency was calculated for light flashes induced in the dark-adapted eye by Cerenkov radiation from the flux of heavy nuclei that exists in space beyond the geomagnetic field. The expected frequency of light flashes depends on the threshold number of photons that must be absorbed in a rod cluster. The results of the calculation are presented as a curve of the mean frequency of light flashes versus the threshold number of absorbed photons. The results are not sensitive to variations in the path length from 5 to 15 grams per square centimeter of water-equivalent before the nucleus reaches the retina. Calculations were based on the fluxes and energy spectra of galactic cosmic ray nuclei of helium to iron, measured at a time of minimum solar modulation. The expected light flash frequencies induced by Cerenkov radiation are consistent with the frequencies reported by the astronauts on Apollo missions 11 through 14.
A self-consistent model for cosmic-ray hydrogen and helium propagation from the sources in the Galaxy to the orbit of earth is obtained, taking into account experimental information now available on the isotopes H-1, H-2, He-3, and He-4. The only adjustable parameters include the shape of the energy spectra of H-1 and He-4 at the time of source injection, the distribution of particle path lengths in interstellar space, and the solar modulation parameters. It is found that the allowed form of the source differential spectra of the H-1 and He-4 nuclei is dominated by a power law in total energy.
The neutron measurements with the OGO-6 spacecraft are reported. Topics discussed include: the design and calibration of a neutron monitor for measuring the cosmic ray neutron leakages from the earth's atmosphere, determination of latitude dependence of cosmic ray leakage flux, determination of the angular distribution of neutron leakage flux as deduced by measurements of the altitude dependence, and verification of the solar modulation of the cosmic ray source for the neutron leakage.