Cosmic radiation monitoring at low-Earth orbit by means of thermoluminescence and plastic nuclear track detectors

Abstract

Cosmic radiation represents one of the main health issues for astronauts during space missions. To evaluate the impact of space radiation on human health and to reduce the uncertainty of related cancer risk, it is important to determine the exposure level as accurately as possible. Due to complexity of radiation environment in space and behind the shielding, accurate data cannot be obtained using only calculations; experimental measurements in real flight conditions are also necessary.In this contribution we present results obtained during two space missions – onboard International Space Station (during 2012–2013) and onboard biosatellite BION-M1 (April–May 2013). In both cases, packages containing thermoluminescent and plastic nuclear track detectors were placed at various locations onboard ISS/BION-M1. Spectra of linear energy transfer, absorbed doses, and dose equivalents are discussed with respect to orbit parameters and shielding.For both missions, dose characteristics can differ by a factor of about 2, depending on the location. Due to higher altitude and limited shielding, absorbed dose and dose equivalent inside BION-M1 are significantly higher than inside ISS – whereas inside ISS the maximal value of measured dose equivalent rate was about 1 mSv/day, inside BION-M1 it exceeded 3 mSv/day. Outside the capsule it was about two times higher than inside the capsule.