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With a remarkable tolerance to high-energetic radiation and potential high power-to-weight ratios, halide perovskite-based solar cells are interesting for future space PV applications. In this work, we fabricate and test methylammonium-free, co-evaporated FA0.7Cs0.3Pb(I0.9Br0.1)3 perovskite solar cells that could potentially be fabricated in space or on the Moon by physical vapor deposition, making use of the available vacuum present. The absence of methylammonium hereby increased the UV-light stability significantly, an important factor considering the increased UV proportion in the extra-terrestrial solar spectrum. We then tested their radiation tolerance under high energetic proton irradiation and found that the PCE degraded to 0.79 of its initial value due to coloring of the glass substrate, a typical problem that often complicates analysis. To disentangle damage mechanisms and to assess whether the perovskite degraded, we employ injection-current-dependent electroluminescence (EL) and intensity-dependent VOC measurements to derive pseudo-JV curves that are independent of parasitic effects. This way we identify a high radiation tolerance with 0.96 of the initial PCE remaining after 1 × 1013 p+ cm-2 which is beyond today's space material systems (

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The HZB cyclotron has treated more than 4000 patients with eye tumors using protons. The accelerator can also provide heavier ions which could be suitable for ocular radiation therapy. Helium ions exhibit less lateral spread, increased relative biological effectiveness and a sharper Bragg-Peak compared to protons of the same range, while minimizing nuclear fragmentation and thus excessive dose downstream the irradiated volume compared to more heavy ions. When accelerating fully stripped helium ions (alpha particles), hydrogen molecular ions can also be accelerated to the same energy with a small tuning of the machine due to having almost the same mass-to-charge ratio, yielding a proton beam of double current after the beam exits the vacuum window towards the target. The acceleration and characterization of these two ion species are described in this paper, suggesting the feasibility of a corresponding clinical cyclotron for ocular or even deep-seated tumors., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

The HZB cyclotron has been providing protons for eye-tumor treatment for more than 20 years. While it has been very successful using conventional dose rates (15-20 Gy/min), recent studies indicate that rapid irradiation with very high dose rates (FLASH) might be equally efficient against tumors but less harmful to healthy tissues. The flexible operation schemes of the HZB cyclotron can provide beams with variable intensities and time structures, covering a wide unexplored regime within the FLASH requirements (>40 Gy/s in 500 ms). This paper presents the results of the first FLASH beam production at HZB towards the establishment of an in-vivo clinical irradiation in the future., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

Beside the Therapy station for ocular tumors we have an experimental area to deliver protons and other ions. At this place there is also the possibility to do High Energy Pixe measurements on samples from cultural heritage. The positioning of the samples under test is possible by means of an xy-table with an range of 500x500 mm² and a load of at least 50 kg, reproducibility ±0.1 mm. We can change the beam size between 1 mm diameter as focused beam and up to 50 mm diameter with different scattering foils and homogeneous dose spread. We can deliver beam intensities from single protons up to 10¹² protons/cm² * sec The energy can be set to 68 MeV with a single Bragg peak, spread out Bragg peaks with a mechanical range shifter or absorber plates to reduce the energy. The timing properties range from quasi DC to a single pulse width of 1 ns with a repetition rate up to 2.4 MHz. Instead of a scattering foil to increase the beam spots we also can use beam scanning with the focused beam to reduce the beam losses. We will show the different beam properties at the experimental target area for radiation hardness testing of solar cells, optical elements and electronics under test., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

For more than 20 years eye tumours are treated in collaboration with the Charité - Universitätsmedizin Berlin. The close co-operation between Charité and HZB permits joint interdisciplinary research. Irradiations with either a sharp, well focused or a broad beam, either in vacuum or in air are possible. In addition, a 60Co-source for gamma-irradiations is available. Experiments now comprise dosimetry, detector comparisons, ambulant mouse irradiations, including class I gene-modified mice. Furthermore, radiation hardness tests on detectors, CCD-cameras and other electronics are performed. In order to improve the beam diagnosis between the 2 MV injector Tandetron and the cyclotron a harp has been installed, leading to new beam line calculations for the injection line. The accelerator operation for therapy as well as on-going experiments and results will be presented., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

Ocular melanomas have been treated for the last 20 years at the Helmholtz-Zentrum Berlin in collaboration with the Charité Universitätsmedizin Berlin. However, parts of the initial control system electronics date back to the 1970s, when the machine was installed. Facing a critical shortage of legacy and obsolete components and with the down-time due to failures in the electronics on the increase, a decision was made to install the digital low-level RF control system, developed by iThemba LABS, on our K=132 cyclotron. A short description of the installation and commissioning process, which occurred in April 2017, and the experiences of the first 2 years of operation with the new digital low-level RF control system is presented., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

In collaboration with the research reactor in Berlin, the Helmholtz-Zentrum für Materialien und Energie, the Gemäldegalerie Berlin is the only institute worldwide, which systematically employs the method of Neutron-Activation-Autoradiography to analyze paintings. Today we have investigated about 70 paintings. This is an effective, non-destructive, however, exceptional method for the investigation of paintings and paint techniques. It allows the visualization of structures and layers beneath the top surface and, in addition, enables the identification of elements contained in the pigments. The instrument B8 at the research reactor BER II is dedicated to this research. It allows to irradiate and activate artistic, technical, or geological items (foils, stones, etc.) and other materials with cold neutrons having a flux of On = 1 x 109 cm-2 s-1 and to investigate it afterwards with imaging plate technique and / or to analyse it with gamma spectroscopy. The irradiation process, the investigation of the induced radioactivity and the possible identification of the pigments are presented., Restaurierung und Archäologie, Bd. 8 (2015): Restaurierung und Archäologie