Development and Exploitation of a Novel Multi-Purpose Particle Detector for Radiation Monitoring in Space Exploration

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Radiation monitoring and protection are key topics in medical physics and are of particular relevance to manned space exploration. Current radiation detection technologies lack capabilities that are crucial to ensure astronaut safety on journeys beyond Earth’s protective atmosphere, such as to the moon or Mars. A precise knowledge of the composition of cosmic radiation is important to understand the biological effectiveness of radiation and to develop better shielding technologies.We are developing a new detector concept, called the Multipurpose Active-target Particle Telescope (MAPT), that combines many of the advantages of currently used systems and overcomes many of their limitations. We use state-of-the-art photosensors and scintillators to construct a compact, lightweight device with low power consumption that can measure energy and direction for individual particles with a quasi-omnidirectional acceptance. With its novel detector concept, MAPT can better identify particle species than traditional particle telescopes at energies below 1 GeV/n. While being less powerful than a complex spectrometer, it would be significantly simpler to construct and operate. This has both scientific and operational advantages.We plan to deploy a technology demonstration experiment to the International Space Station (ISS) in cooperation with U.S.-based partners. If successfully proven, MAPT could replace most stationary radiation detectors that are currently in use on the ISS. Its design also allows a more flexible deployment throughout the station. Future deep-space missions could be equipped with slightly modified versions of MAPT, accounting for each mission’s requirements.Besides comparing the instrument’s capabilities to existing devices, the experiment shall provide data that is so far unavailable. We plan to measure the composition, the energy and angular spectra, and particle species-specific flux profiles of cosmic radiation in real time. MAPT’s unique capabilities also allow us to take correlated measurements of charged primary radiation and (charged and uncharged) secondary radiation that is for example created in interactions of cosmic rays with the spacecraft. The accessible energy range of 25 MeV/n to about 1 GeV/n is particle species-specific.Data obtained by us could be supplemented and combined with laboratory measurements of the impact of different radiation particles at the cellular level, helping to further the understanding of the effects of highly-ionizing radiation, e.g. high-energy atomic nuclei, on astronauts. Large uncertainties in this area are the main factor driving limitations on mission durations.The MAPT concept also provides many features that allowing applications in other fields. Among these are excellent energy resolution at energies relevant to radiation therapy through precise determination of the specific energy loss and the identification of antiparticles at very low energies out of reach for other detector concepts.