Speaker
Dr
Olivier Van Hoey
(The Belgian Nuclear Research Center SCK-CEN)
Description
Radiation dose rates in space are two orders of magnitude higher than on earth. This impacts human health and instrumentation performance. Also biological experiments are affected. Therefore, dose assessment in space is of primordial importance. The radiation field in space is also more complex than on earth. Therefore, precise dose assessment can only be performed by combining computer simulations and measurements.
Radiation measurements in space typically rely on bulky, complex and expensive active monitors providing real time information on the intensity and composition of the radiation field. However, also compact and cheap passive detectors are useful as they don't require power and are easily made in sub-cm dimensions. This is convenient for detailed mapping, dose assessment for biological experiments and organ dose assessments using anthropomorphic phantoms.
SCK•CEN has strong expertise in passive optically and thermally stimulated luminescent detectors (Luxel, LiF:Mg,Ti, LiF:Mg,Cu,P). Reading is performed in specialized labs with the commercial Harshaw 5500 for thermoluminescent detectors and a homemade laser system for optically stimulated luminescent detectors. The reading and analysis protocols are optimized based on detector characterization by radiation transport simulations and irradiations in our calibration lab and at ion beam facilities.
In the framework of the international DOSIS and DOSIS 3D projects we have been sending our detectors to the ISS typically every 6 months since 2009 for mapping of the dose rates in the Columbus module. Further, we have regularly been sending our detectors together with biological experiments on the inside and outside of the ISS and inside other spacecraft such as FOTON-M4 and BION. These measurements have shown dose rates expressed in terms of absorbed dose in water between 100 and 1000 µGy/day and a strong dependence on altitude and inclination of the orbit, solar cycle and shielding.
Primary author
Dr
Olivier Van Hoey
(The Belgian Nuclear Research Center SCK-CEN)
Co-authors
Mr
Alessio Parisi
(The Belgian Nuclear Research Center SCK-CEN)
Dr
Filip Vanhavere
(The Belgian Nuclear Research Center SCK-CEN)
