ISS RADIATION ENVIRONMENT AS OBSERVED BY LIULIN TYPE-R3DR2 INSTRUMENT IN OCTOBER-NOVEMBER 2014

Abstract

Space radiation was monitored using the R3DR2 spectrometer-dosimeter during the flight outside the Russian “Zvezda” module of ISS in October-November 2014. The instrument was mounted on the ESA EXPOSE-R2 platform. The R3DR2 instrument was first developed and used during the flight of ESA EXPOSE-R platform in 2009-2010 (Dachev et al, 2015a). It is a low mass, small dimension automated device that measures solar visible and ultraviolet (UV) radiation in four channels and ionizing radiation in 256 channels of a Liulin-type energy deposition spectrometer (Dachev et al, 2002). Ionizing radiation was measured and separated in 256 deposited energy spectra, which were further used for determination of the absorbed dose rate and flux. The main results obtained by the R3DR2 instrument are: (1) three different radiation sources were detected and quantified - galactic cosmic rays (GCR), energetic protons from the inner radiation belt (IRB) in the region of the South Atlantic anomaly and energetic electrons from the outer radiation belt (ORB); (2) for the first time in the history of using of the Liulin-type energy deposition spectrometers (Dachev et al, 2015b) an observable flux from solar energetic particles (SEP) was detected in the period 1-4 November 2014; (3) the obtained SEP energy deposition spectra were compared with other spectra to confirm their shape.