Radiation measurement on the International Space Station

The results of an investigation of radiation environment on board the ISS with apogee/perigee of 420/380 km and inclination 51.6° are presented. For measurement of important characteristics of cosmic rays (particles fluxes, LET spectrum, equivalent doses and heavy ions with Z⩾2) a nuclear photographic emulsion as a controllable threshold detector was used. The use of this detector permits a registration of the LET spectrum of charged particles within wide range of dE/dx and during last years it has already been successfully used on board the MIR station, Space Shuttles and “Kosmos” spacecrafts. An integral LET spectrum was measured in the range 0.5-2.2×103keV/μm and the value of equivalent dose 360μSv/day was estimated. The flux of biologically dangerous heavy particles with Z⩾2 was measured (3.85×103particles/cm2).