Speaker
Description
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Design and in-silico benchmarking of proton beam degraders for trapped protons in Low Earth Orbit
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Jayden T. Rinaldo1*, Nils Krah2, Soon Hock Ng1, Matthew J. Large1, Rebecca Allen3, Konstantinos P. Chatzipapas4 & Jeremy M.C. Brown1
1 Optical Science Centre, Swinburne University of Technology, Hawthorn, Australia
2 Department of Research and Development, Holland Proton Therapy Centre, Delft, Netherlands
3 Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Australia
4 Department of Radiation Science and Technology, Technical University of Delft, Delft, The Netherlands
Themes: Technology transfer from ground-based applications, Approach to risk management for small satellites/ cube-sats, Radiation shielding modelling.
Ionising space radiation found in Low Earth Orbit (LEO) contributes to degradation and potential failure of electrical components within orbiting satellites [1]. Experimental space radiation testing is vital for assessing unqualified components. This typically involves exposing susceptible components to multiple monoenergetic beams of protons and electrons at several pre-determined energies [2]. However, such experimental testing, particularly for low budget CubeSat and SmallSat missions, is often disregarded due to limited access to testing facilities and restricted funding [3]. Omitting crucial radiation testing from the design process can lead to unplanned spacecraft failure, resulting in these missions contributing to space junk and pollution in LEO [4].
This work presents a practical and reproducible method of emulating the trapped proton spectrum in LEO through design of proton beam degraders, comparable to degraders utilised for radiotherapy purposes [5]. These degraders would allow for space qualification testing from a single beam exposure rather than multiple exposures at single energies, reducing the required beamtime and hence the associated testing costs. Additionally, this method demonstrates the potential for adaptation of existing medical based proton facilities for space radiation testing, enabling easier access to space radiation testing. Degraders were designed and validated using a simulated model of the Holland Proton Therapy Centre Research and Development (HPTCR&D) beamline using OpenGATE10 [6]. Using the HPTCR&D OpenGATE10 beamline model depicted in Figure 1, a database of proton kinetic energy flux spectra scored from multiple thicknesses of PMMA was constructed. Reference trapped proton energy spectra were obtained from the European Space Agency’s (ESA) Space Environment Information System (SPENVIS) [7]. To validate degrader performance, proton kinetic energy spectra, dose uniformity, and Linear Energy Transfer were explored. For experimental validation, the optimised proton beam degraders will be 3D-printed and deployed at the HPTCR&D beamline.
![Figure 1. OpenGATE10 model of the HPTCR&D beamline (top), with accompanying experimental apparatus (bottom) appropriated from Swinburne University of Technology [8], Components included are: Kapton exit window (1), Scattering foil (2), Beam monitor (3), Dual scattering ring (4), First collimator (5), Second collimator (6), Detector stage (7).][9]
[1]. Gutiérrez, O., Prieto, M., Perales-Eceiza, A., Ravanbakhsh, A., Basile, M. and Guzmán, D., 2023. Toward the use of electronic commercial off-the-shelf devices in space: Assessment of the true radiation environment in low earth orbit (leo). Electronics, 12(19), p.4058.
[2]. Rajkowski, T., Saigne, F. and Wang, P.X., 2022. Radiation qualification by means of the system-level testing: Opportunities and limitations. Electronics, 11(3), p.378.
[3]. Bouwmeester, J., Menicucci, A. and Gill, E.K., 2022. Improving CubeSat reliability: Subsystem redundancy or improved testing?, Reliability Engineering & System Safety, 220, p.108288.
[4]. Maclay, T. and Mcknight, D., 2021. Space environment management: Framing the objective and setting priorities for controlling orbital debris risk. Journal of Space Safety Engineering, 8(1), pp.93-97.
[5]. Simeonov, Y., Weber, U., Schuy, C., Engenhart-Cabillic, R., Penchev, P., Durante, M. and Zink, K., 2021. Monte Carlo simulations and dose measurements of 2D range-modulators for scanned particle therapy. Zeitschrift für Medizinische Physik, 31(2), pp.203-214.
[6]. Sarrut, D., Arbor, N., Baudier, T., Bert, J., Chatzipapas, K., Favaretto, M., Fuchs, H., Grevillot, L., Harb, H., Van Hoey, G. and Jacquet, M., 2026. GATE 10 Monte Carlo particle transport simulation: I. Development and new features. Physics in Medicine & Biology, 71(1), p.015042.
[7]. European Space Agency (ESA) and the Royal Belgian Institute for Space Aeronomy, “SPENVIS,” 2024. https://www.spenvis.oma.be/intro.php.
[8]. Swinburne University of Technology. Space Radiation Effects, 2025. https://www.swinburne.edu.au/research/institutes/space-technology-industry/space-radiation-effects/
[9]. https://liveswinburneeduau-my.sharepoint.com/my?viewid=793fc621%2D5652%2D429c%2Db34a%2D8fce33b13e98&id=%2Fpersonal%2Fjrinaldo%5Fswin%5Fedu%5Fau%2FDocuments%2FImages%2FFigure1%2Epng&parent=%2Fpersonal%2Fjrinaldo%5Fswin%5Fedu%5Fau%2FDocuments%2FImages