Physical mechanisms of the inner Van Allen belt

This paper attempts to explain how each of the physical processes of the inner Van Allen belt affects the particle distribution function, and to show how it is incorporated into an equation containing terms representing the other known mechanisms. The subject is discussed under the following topics: trapped particle motion in the Earth's magnetic field, treatment of nonadiabatic effects, effects of various physical processes on trapped particle distribution functions (collisions of trapped electrons with atmospheric constituents, albedo neutrons, solar neutrons, nuclear reactions, secular variation of geomagnetic field, radial diffusion, interactions between particles and waves, reversible adiabatic variations), and application of theoretical formulation to inner radiation belt observations (electrons in the inner zone, protons in the inner zone). 27 figures, 1 table