Flux of high-LET cosmic-ray particles in manned space flight

On the Apollo and Skylab missions the high-energy heavy ion (HZE) flux was measured by means of plastic nuclear track detectors. Measurements involved the fluxes of high linear energy transfer (LET), particles with Z between 6 and 26 incident on astronauts and on several biological experiments. Partial results of these measurements are presented; the effects of shielding and solar modulation are discussed.-