Time Profile of Cosmic Radiation Exposure During the EXPOSE-E Mission: The R3DE Instrument

Abstract

The aim of this paper is to present the time profile of cosmic radiation exposure obtained by the Radiation Risk Radiometer-Dosimeter during the EXPOSE-E mission in the European Technology Exposure Facility on the International Space Station’s Columbus module. Another aimis to make the obtained results available to other EXPOSE-E teams for use in their data analysis. Radiation Risk Radiometer-Dosimeter is a low-mass and small-dimension automatic device that measures solar radiation in four channels and cosmic ionizing radiation as well. The main results of the present study include the following: (1) three different radiation sources were detected and quantified— galactic cosmic rays (GCR), energetic protons from the South Atlantic Anomaly (SAA) region of the inner radiation belt, and energetic electrons from the outer radiation belt (ORB); (2) the highest daily averaged absorbed dose rate of 426 μGy d⁻¹ came from SAA protons; (3) GCR delivered a much smaller daily absorbed dose rate of 91.1 μGy d⁻¹, and the ORB source delivered only 8.6 μGy d⁻¹. The analysis of the UV and temperature data is a subject of another article (Schuster et al., 2012).