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Tuzzolino, A. J.

Publications and source records attributed to Tuzzolino, A. J..

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Jupiter revisited - First results from the University of Chicago charged particle experiment on Pioneer 11

The data obtained by Pioneer 11 confirmed results from Pioneer 10 and provided new information for an understanding of the physics of the Jovian magnetosphere. Attention is given to the significance of Pioneer 11 data in relation to two fundamentally different models which have been proposed to account for the variations in the electron flux observed in Jupiter's outer magnetosphere. Proton flux characteristics are considered, taking into account the intensity profiles of energetic particles trapped in the dipole region of Jupiter's magnetic field.

Simpson, J. A.↗
NASA NTRS1975

Characteristics of Jovian trapped electrons and protons for the region within 20 Jupiter radii and their interaction with Io

A brief summary is given of Pioneer 10 observations of trapped particles in the inner-core region (within 20 Jupiter radii) of the Jovian magnetosphere. The three sensor systems used to study trapped radiation in this region are described. Intensity profiles are plotted as a function of magnetic-shell parameter (L) for electrons with energies of at least 3 MeV, protons with energies of at least 35 MeV, and protons with energies between 0.5 and 1.8 MeV. The effect of trapped-particle absorption by Io is clearly seen in the intensity profiles of all the observed particle species, and evidence is presented for preferential absorption of small-pitch-angle particles by Io. Conclusive evidence is given for the fact that Jupiter's trapped radiation is maintained by the inward diffusion of particles across L shells.

Simpson, J. A.↗
NASA NTRS1975

Cosmic ray radial intensity gradients measured by Pioneer 10 and Pioneer 11

The paper reports revised and updated measurements of the cosmic ray radial intensity gradient made with Pioneer 10 and 11 over the radial range 1-5 AU in differential energy windows from 10-70 MeV/nucleon, and for the integral intensity exceeding 70 MeV/nucleon. In most cases small positive gradients are found of the order of a few percent per AU, with evidence for significant temporal variations. Spectral studies show the presence of the 'anomalous' helium component below 50 MeV at all radial distances from 1-5 AU.

Mckibben, R. B.↗
NASA NTRS1974

The protons and electrons trapped in the Jovian dipole magnetic field region and their interaction with Io

Detailed analysis of electrons equal to or greater than 3 MeV and of protons 0.5 to 1.8 MeV and equal to or greater than 35 MeV for both the inbound and the outbound passes of the Pioneer 10 spacecraft. Conclusive evidence is obtained that the trapped radiation in Jupiter's inner magnetosphere is maintained and supplied by inward diffusion from the outer regions of the trapped radiation zone. It is shown that the time required for isotropization of an anisotropic flux by pitch angle scattering inside L approximately equal to 6 is long in comparison with the time required for particles to diffuse inward from L approximately equal to 6 to L approximately equal to 3, that the high-energy protons were not injected at high energies by the Crand (cosmic ray albedo neutron decay) process but were accelerated in the magnetosphere of Jupiter, and that the main conclusions of this analysis are unaffected by use of either the D sub 1 or the D sub 2 magnetic field models. Theoretical studies of the capture of trapped electrons and protons by Io have been carried out, and it is found that the probability of capture by Io depends strongly upon the particle species and kinetic energy.

Simpson, J. A.↗
NASA NTRS1974

Protons and electrons in Jupiter's magnetic field - Results from the University of Chicago experiment on Pioneer 10

Fluxes of high energy electrons and protons are found to be highly concentrated near the magnetic equatorial plane from distances of about 30 to about 100 Jovian radii. The 10-hour period of planetary rotation is observed as an intensity variation, which indicates that the equatorial zone of high particle fluxes is inclined with respect to the rotation axis of the planet. At radial distances below 20 Jovian radii, the synchrotron-radiation-producing electrons with energies above 3 MeV rise steeply to a maximum intensity near the periapsis at 2.8 Jovian radii. The flux of protons with energies above 30 MeV reaches a maximum intensity at 3.5 Jovian radii, with the intensity decreasing inside this radial distance.

Simpson, J. A.↗
NASA NTRS1973

Preliminary Pioneer-10 intensity gradients of galactic cosmic rays.

Selected data from the University of Chicago charged-particle telescope on the Pioneer-10 spacecraft bound for Jupiter have been examined and compared with data from the University of Chicago charged-particle telescopes on the Earth satellites IMP-5 and IMP-6 at 1 AU to derive a preliminary integral intensity gradient for relativistic galactic protons and helium nuclei. The preliminary value obtained is (4.5 plus or minus 1.0) percent per AU over the radial range 1-2.8 AU. Preliminary differential gradients also have been obtained for the energy range 29-67 MeV per nucleon.

Mckibben, R. B.↗
NASA NTRS1968

Silicon detectors aboard Surveyor V.

Conventional and Li-drifted Si charged particle detectors for alpha scattering experiment aboard Surveyor 5 noting operating characteristics, performance and electrical stability

Kristoff, J. J.↗