Comparison of Measured and Calculated High-LET Nuclear Recoil Particle Exposure on Biosatellite III

High-LET nuclear recoil particles encountered during the flight of Biosatellite III were measured by means of a detector packet consisting of tissue-equivalent plastic nuclear track detectors located in the proximity of the animal's brain. The plastic detectors were used to record Z > 2 or Z = 2, nuclear recoil particles, with trajectory lengths, L0 > 10 mi. Some charge resolution, even for the very short track segments, about 10 mi, was found possible. A heavy recoil track density roR(Z > 2, L0 > 10 mi) about lO3 Cm−3 day−1 was measured. This value is in good agreement with a predicted density calculated with the assumption that the tracks are caused by nuclear recoils produced through the inelastic scattering of the trapped protons. The measured results probably correspond only to the high energy tail of the total recoil track distribution.