Analysis of the Radiation Environment on Board the International Space Station Using Data from the SilEye-3/Alteino Experiment
2014 (English)Doctoral thesis, monograph (Other academic)
This thesis presents an analysis of the radiation environment on board the Russian section of the International Space Station (ISS) using data from the SilEye-3/Alteino experiment. As part of the analysis the efficiency and response of the SilEye-3/Alteino detector was studied. The relative nuclear abundance is generally in agreement with expected results. The presence of odd Z nuclei is significantly increased when compared with measurements outside the ISS. However, in ISS-y (Starboard-Ports) and z (Nadir-Zenith) directions an underabundance of carbon and oxygen nuclei is seen, whereasin x (Forward-Aft) there seemes to be an overabundance. One possible explanation is the absence of high-Z material in the ISS module wall for y and z . Whereas in x, most of the main body of the ISS is in front of the detector and the amount of high-Z material (i.e. aluminium) is large. The nalysis of fragmentation of iron into a range of secondary nuclei (15≤Z ≤25) indicates an aluminium hull equivalent thickness of 8-9 cm in y- and z-directions. For x the aluminium hull equivalence amounts to about 17 cm. Flux, LET, dose and dose equivalent rates present a clear anisotropy in the different orthogonal directions of the ISS, with rates consistently lower in x. This effect is more pronounced for the heavy-ion component (LET >50 keV/μm). Measureddose rates vary from 25 μGy/day to 75 μGy/day, depending on location, orientationand configuration of the detector. The dose equivalent varies from 50 μSv/day toalmost 470 μSv/day.The shielding effect of the polyethylene amounts to 25-37% dependent on loca-tion and orientation inside the ISS. The majority of the reduction occurs duringpassages through the SAA. A Geant4 comparison with the Phits simulations code have been preformed as an initial survey into the treatment of hadronic physics for heavy ions in Geant4.
Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2014. , x, 103 p.
TRITA-FYS, ISSN 0280-316X ; 2014:25
Space Radiation, ISS, Alteino, Geant4
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:kth:diva-145339ISBN: 978-91-7595-178-2OAI: oai:DiVA.org:kth-145339DiVA: diva2:717764
2014-06-05, Sal F3, Lindstedtsvägen 26, KTH, Stockholm, 10:00 (English)
Seiringer, Robert, Professor
Lund-Jensen, Bengt, Professor
QC 201405212014-05-212014-05-162014-05-21Bibliographically approved