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Results for “PROTON BELT”

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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At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

The influence of ionization events on atmospheric ozone

Atmospheric ionization events can modify the concentration of neutral species in the stratosphere and mesosphere. In particular, ozone is destroyed because of the production of significant quantities of odd nitrogen and hydrogen compounds which react photochemically to destroy ozone. Direct evidence of ozone depletion comes from data taken during and following two solar flares generating large fluxes of 10-100 Mev protons, which bombarded the polar stratosphere and mesosphere. Observations of ozone taken during X-ray emission by solar flares and energetic electron precipitation during aurorae indicates ozone destruction above 50 km by ionization produced odd hydrogen. Lightning is apparently a large contributor to the tropospheric odd nitrogen budget. Ion propulsion induced dumping of the inner proton radiation belt represents a human activity which may influence stratospheric NOx.

Aikin, A. C.↗
NASA NTRS1974

Jupiter's radiation belts

Fluxes of electrons and protons in Jupiter's radiation belts are calculated with the source (radial diffusion inward from the solar wind) and the loss (synchroton radiation). The calculations are tested against the measured radio-wave wavelength distribution, the radio-wave distribution with distance from Jupiter, and the degree of polarization of the radio waves. The Fokker-Planck equation is solved by using the method of Farley and Walt (1971) with the fixed flux at the outer boundary and the zero flux at Jupiter's surface. It is found, in agreement with Brice and McDonough (1973), Jacques and Davis (1973), and Birmingham et al. (1974), that the usual magnetic and electric diffusions, which vary as L to the 10th power and L to the 6th power, respectively, are insufficient to furnish the required electrons and that the diffusion driven by ionospheric winds of Brice and McDonough is strong enough to furnish Jupiter's belts. An additional loss mechanism close to Jupiter is required to remove the electrons, particularly those at low energies.

Stansberry, K. G.↗
NASA NTRS1994

Recent space shuttle observations of the South Atlantic anomaly and the radiation belt models

Active ingredients consisting of Tissue Equivalent Proportional Counter (TEPC) and a Proton and Heavy Ion Detector (PHIDE) have been carried on a number of Space Shuttle flights. These instruments have allowed us to map out parts of the South Atlantic Particle Anomaly (SAA) and to compare some of it's features with predictions of the AP-8 energetic proton flux models. We have observed that consistent with the generally observed westward drift of the surface features of the terrestial magnetic field of the SAA has moved west by about 6.9 degrees longitude between the epoch year 1970 of the AP-8 solar maximum model and the Space Shuttle observations made twenty years later. However, calculations indicate that except for relatively brief periods following very large magnetic storms the SAA seems to occupy the same position in L-space as in 1970. After the great storm of 24 March 1991 reconfiguration of the inner radiation belt and/or proton injection into the inner belt, a second energetic proton belt was observed to form at approximately equal to 2. As confirmed by a subsequent flight observations, this belt was shown to persist at least for six months. Our measurements also indicate an upward shift in the L location of the primary belt from L = 1.4 to L = 1.5. In addition we confirm through direct real time observations the existence and the approximate magnitude of the East-West effect. If the need exists for improved and updated radiation belt models in the Space Station era, these observations point out the specific features that should be considered and incorporated when this task is undertaken.

Konradi, A.↗
NASA NTRS1974

Stably trapped proton fluxes in the Jovian magnetosphere

A model of the energetic proton fluxes in the Jovian magnetosphere is constructed based on the inward radial diffusion of protons from the solar wind and the plasma turbulent precipitation loss of protons from the radiation belts. Outside 12 Jovian radii the proton fluxes follow a loss-free radial diffusion profile. Inside 12 Jovian radii the proton fluxes should be near the stably trapped limit flux set by convective marginal stability to the electromagnetic ion cyclotron wave and the quasi-electrostatic ion loss-cone wave.

Coroniti, F. V.↗
NASA NTRS1986

Single-Event Upsets Caused by High-Energy Protons

Heavy secondary ions do not significantly alter device responses. Conclusion that external reaction products cause no significant alteration of single-event-upset response based on comparison of data obtained from both lidded and unlidded devices and for proton beams impinging at angles ranging from 0 degrees to 180 degrees with respect to chip face. Study also found single-event-upset cross section increases only modestly as proton energy increased to 590 MeV, characteristic of maximum energies expected in belts of trapped protons surrounding Earth and Jupiter.

Price, W. E.↗
NASA NTRS1961

The Flux and Energy Spectra of the Protons in the Inner Van Allen Belt

A cylindrical stack of G-5 nuclear emulsions housed in the payload section of a four-stage research rocket was flown into the northern edge of the inner Van Allen belt on September 19, 1960. The experimental design permitted, for the first time, measurements of the particle fluxes and energy spectra as functions of position along the rocket trajectory. Eight points along the trajectory have been selected for analysis. Results are presented herein for three of these points, and they are discussed in the light of various theories on the trapped radiation.

Naugle, John E.↗