Carlos Granja1, L. Mikulickova2, V. Marsikova3, D. Doubravova1, R. Pavlica4, A. Marek5, A. Inneman3,
J. Pokorny3, M. Sommer6, M. Urban7, J. Stursa6, V. Zach6, P. Krist6, D. Chvatil6, V. Olsansky6
1 Advacam, Prague, Czech Republic
2 TTS, Prague, Czech Republic
3 Rigaku, Prague, Czech Republic
4 5M, Kunovice, Czech Republic
5 HVM Plasma, Prague, Czech Republic
6 Nuclear Physics Institute, Czech Academy of Sciences, Prague, Czech Republic
7 Czech Technical University, Faculty of Electrical Engineering, Prague, Czech Republic
We study the radiation response and shielding effectiveness of composite materials customized for spacecraft and aerospace applications. We use different types of radiations at selected fluxes, energies and geometry. Measurements were performed in defined fields with X-rays (RTG units, broad spectrum up to 150 keV), gamma rays (discrete spectrum, 60Co source – 1173 keV, 1333 keV), electrons (10–20 MeV) and protons (10–30 MeV). The technique measures in detail the transmitted radiation field behind the targets which also contains induced secondary radiation – see Fig. 1a. Changes in the flux, dose rate, composition, spectrum, LET spectra, spatial distribution and beam size/profile are registered – see Fig. 1b,c,d. Such detailed studies are made possible by the high-resolution position- and spectral-sensitive semiconductor pixel detector Timepix [1-3]. We used the detector in a miniaturized camera Minipix-Timepix architecture (full size 75mm × 16mm × 10mm). Samples studied included composite materials and glass-based samples as well as conventional shielding materials (Al, plastic, Copper, Lead).
Figure 1: (a) Illustration of principle of technique. Radiation field at the detector position for (b) bare/free beam, i.e. no target, and for two selected samples (c, d). Full sensor size shown (14mm×14mm). Data registered by a MiniPix-Timepix 300 µm Si detector for 31 MeV protons produced at the NPI Prague Cyclotron.
 C. Granja, J. Jakubek, S. Polansky, et al., Resolving power of pixel detector Timepix for wide-range electron, proton and ion detection, Nuclear Instr. Methods A 908 (2018) 60-71.
 C. Granja, K. Kudela, J. Jakubek, et al., Directional detection of charged particles and cosmic rays with the miniaturized radiation camera MiniPIX Timepix, Nuclear Instr. Methods A 911 (2018) 142-152.
 X. Llopart, R. Ballabriga, M. Campbell, Timepix, a 65 k programmable pixel readout chip for time, energy and/or photon counting measurements, Nucl. Instrum. Methods Phys. Res. A 581 (2007) 485–494.
Research carried out for Project 40001250020/18/NL/GLC/hh of the European Space Agency/ESA. Measurements at the NPI Prague Cyclotron were performed in frame of the CANAM Research Infrastructure Grant Project LM2011019 of the MSMT Ministry of the Czech Republic.