Protons from 40 to 110 Mev observed on Injun 3

The spatial distributions and time behavior of 40- to 110-Mev trapped protons were observed for approximately nine months on the Injun 3 satellite. Time decay was observed only at the lower edges of the inner belt; extremely stable intensities were observed elsewhere in the region R <1.5 earth radii. Assuming that an equilibrium proton distribution is established from albedo neutron injection and Coulomb energy loss with the atmosphere, the omnidirectional flux expected from 40 to 110 Mev is calculated for lines of force labeled by L = 1.25 and 1.50. The ratio of the observed unidirectional flux to the calculated value provides a measure of the fraction of neutron decay protons that are trapped.