Accession Number : AD0766463

Title :   A Study of Equatorial Inner Belt Protons from 2 to 200 MeV.

Descriptive Note : Technical rept.,

Corporate Author : CALIFORNIA UNIV RIVERSIDE INST OF GEOPHYSICS AND PLANETARY PHYSICS

Personal Author(s) : Claflin,E. S. ; White,R. S.

Report Date : 06 AUG 1973

Pagination or Media Count : 34

Abstract : The diffusion theory of inner belt protons is extended to lower energies for comparison with the data of Hovestadt et al. The effects of Coulomb energy loss, nuclear inelastic scattering, and the secular decrease of the earth's magnetic field are included. The Farley and Walt solar cycle averaged atmosphere and a neutron source based on the most recent measurements are used. It is found that diffusion theory can account for the observed flux of low energy protons provided that the diffusion coefficient increases at smaller values of the first invariant. This result is interpreted as additional evidence for the importance of electrostatic field fluctuations in causing radial diffusion. It is also found that the excess of protons predicted by the theory at and above 400 MeV/gauss cannot be attributed to pitch angle scattering. Increasing the free electron density by a factor of 5 improves agreement between theory and experiment. (Author)

Descriptors :   (*VAN ALLEN RADIATION BELT, *PROTONS), DIFFUSION, PROTON SCATTERING, GEOMAGNETISM, TROPICAL REGIONS

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE