Accession Number : AD0766408

Title :   Geomagnetically Trapped Alpha Particles. The Inner Zone.

Descriptive Note : Rept for May 73-Feb 73,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s) : Blake,J. Bernard ; Fennell,Joseph F. ; Schulz,Michael ; Paulikas,George A.

Report Date : 28 SEP 1973

Pagination or Media Count : 37

Abstract : The inner-zone population of trapped alpha particles in the energy range 2.14-9.0 MeV was measured during 1969. The measurements show that inner-zone alpha particles are strongly peaked in pitch angle and the intensity decreases rapidly with decreasing L value. The alpha-particle spectra are flat and closely resemble inner-zone proton spectra at comparable energies. The alpha/p ratio is roughly independent of L (1.6 approximately < L approximately < 2.0)and energy (0.293-1.14 MeV/nucleon) and is approximately 1-4 X 0.001. The computed alpha-particle distribution function strongly suggests that the inner zone is populated by alpha particles which diffuse inward conserving M and J. A value of the diffusion coefficient is derived, D(LL) = (1.2 x 10 to the minus 8th power) (L to the 10th power)/day, which is in good agreement with earlier proton studies. (Author)

Descriptors :   (*VAN ALLEN RADIATION BELT, ALPHA PARTICLES), MAGNETOSPHERE, IONS, DISTRIBUTION FUNCTIONS, SCIENTIFIC SATELLITES

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE